This is a bugfix for the following case:

```
# app/models/foo.rb
module Foo; end

# app/models/bar/foo.rb
class Bar::Foo < Activerecord::Base; end
```

Where `Bar::Foo` would never get annotated.

This is an addition to this PR: https://github.com/ctran/annotate_models/pull/692
I've seen it's been stale for a while and it's rather simple fix.

I noticed my ActiveAdmin resources are not being annotated.
I know ActiveAdmin uses plural model names, but, as far as I remember, they used to use singular model names in the past.

We can see some "evidence" of that here: https://activeadmin.info/2-resource-customization.html#customizing-parent-menu-items
Probably in other places as well.

In order to keep the gem working as expected for singular ActiveAdmin resources, I suggest we annotate both singular and plural model names.

I just tested this out in a project of mine where I renamed one file to be in singular form and left the other files in plural form.
It worked like a charm. :)

Currently, the models annotator automatically attempts to find a class with a matching name at the bottom of project's directory tree before going up into specific engine's models.  This causes issues with models that share names with classes in other engines or lower classes in the project's directory.   This PR adds the option to skip attempts to load classes from lower directories and just uses the model's file path directly. 

#674 

AnnotateModels is fat and so hard to maintain.

In order to reduce code lines of AnnotateModels, move constants and methods defined in AnnotateModels to another namespace AnnotateModels::FilePatterns.

Closes #778 

If a column comment includes the newline character, the newline character
would be "printed" into the annotation block resulting in a line break
and an uncommented line.

For example, for the following table:

```
create_table "users", force: :cascade do |t|
  t.string "name", comment: "This is a comment.\nWith two lines!"
  t.datetime "created_at", precision: 6, null: false
  t.datetime "updated_at", precision: 6, null: false
end
```

annotating the model with the `--with-comment` flag will result in:

```
\# == Schema Information
\#
\# Table name: users
\#
\#  id                                       :bigint           not null, primary key
\#  name(This is a comment.
With two lines!) :string
\#  created_at                               :datetime         not null
\#  updated_at                               :datetime         not null
\#
```

This uncommented line would result in invalid Ruby and cause the file to
no longer be valid.

This fix replaces the newline character with an escaped version, so the
output will look more like:

```
\# == Schema Information
\#
\# Table name: users
\#
\#  id                                       :bigint           not null, primary key
\#  name(This is a comment.\nWith two lines!):string
\#  created_at                               :datetime         not null
\#  updated_at                               :datetime         not null
\#
```

I noticed that `AnnotateRoutes` can be more maintainable by refactoring.

I am planning to refactor `AnnotateRoutes` in this order.
*   separate logic of `AnnotateRoutes` into `AnnotateRoutes::HeaderGenerator`.
*   add methods to `AnnotateRoutes::HeaderGenerator` and refactor methods.
*   add `AnnotateRoutes::AnnotationProcessor` and `AnnotateRoutes::RemovalProcessor`

The final goal of this refactoring is as follows.
* https://github.com/nard-tech/annotate_models/blob/feature/refactor_annotate_routes/processors/lib/annotate/annotate_routes.rb
* https://github.com/nard-tech/annotate_models/tree/feature/refactor_annotate_routes/processors/lib/annotate/annotate_routes

So in the first I added `AnnotateRoutes::HeaderGenerator` in order to separate logic of `AnnotateRoutes` in this PR.

When refactor of `AnnotateRoutes` is finished, I would like to refactor `AnnotateModels` in a like way.

## Problem

I have some files in the "models" directory that are not true a `Class`. For example, a [`dry-types`](https://dry-rb.org/gems/dry-types/1.2/sum/) sum type:

```ruby
# app/models/foo.rb
Foo = Types::String | Types::Integer
```

This results in the following line when I annotate.

```
Unable to annotate app/models/foo.rb: undefined method `<' for #<Dry::Struct::Sum:0x00007ff2dd262988>
```

Not a blocking issue but somewhat annoying nonetheless.

## Solution

When annotating a file, check that the file's object is a `Class` to ensure it has the interface we expect.

This PR does the following:
* moves code coverage generation to happen when `COVERAGE` environment variable is present.
* makes integration tests run when when `INTEGRATION_TESTS` is present.
* moves `ruby-head` from TravisCI build. Previously the configuration allowed for `ruby-head` to be ignored if it failed, but it conflicted with the gem release build job step.

It was reported in https://github.com/ctran/annotate_models/issues/762 that column defaults were broken. This reverts changes made in #677 to restore the expected behavior of column defaults. 

For the time being columns with associated enums won't be working.

This is the final completed version of refactoring AnnotateRoutes.

* Fix new lines after comments for rubocop compatability

Fix #552, #607 

The test cases of AnnotateModels.get_schema_info was separated into two sections.
So I merged them into one, and refactor test cases.

This PR is new version of #741.

Refactor test cases for entire rewrite in the future.

Refactor of test cases for AnnotateRoutes.remove_annotations after #736.

Refactor test cases for AnnotateModels.get_schema_info with Globalize gem

I fixed message to make them more natural English.

Refactor RSpec for AnnotateModels (4) - AnnotateModels.get_schema_info (without custom options) (#735)

I refactored test cases of AnnotateModels without custom options.

I refactored RSpec file for another large scale refactor in another PR.

The scope of this pull request is to allow annotate_models to generate models documentation using YARD. This is the first step, I'll add more features later.

* Structuralize RSpec test cases of AnnotateModels.get_schema_info (with custom options)

* Replace expression expansion to plain text

* Refactor RSpec test cases of AnnotateModels.get_schema_info (with custom options)

* Change position of test cases

* Add columns managed by Globalize gem

Globalize hooks into the model and removes the translated columns
from the `klass.columns`. This commit checks if globalize is
hooked into the model and adds the necessary columns to the
annotation array.

* Disable Rubocop Metrics/BlockLength for spec files

RSpec spec files can contain long blocks easily because
of the outher describe methods. So this rule makes not too much
sense for these files.

I refactored and structuralized RSpec test cases of AnnotateModels for readability and scalability because it was too complex to read.

cf. #718 
In this PR, I refactored test cases of some methods in `AnnotateModels`.
I will refactor test cases of other methods in another PR.

I refactored `AnnotateRoutes.routes_exists?` and methods using this.
The points are as follows.

*   Removing `puts` in `AnnotateRoutes.routes_exists?`
*   Using `File.exist?` instead of `File.exists?` because `File.exists?` is deprecated
*   Renaming `AnnotateRoutes.routes_exists?` to `AnnotateRoutes.routes_file_exists?` in order to make the name of method more explanatory

This change converts .all_options into a constant and moves it into Annotate::Constants. It also changes usages of .all_options.

Same problem returned by @janosrusiczki in #430

Spatial columns with activerecord-postgis-adapter (5.2.2) are not displayed nice

```
# name           :string(3)
# active         :boolean          default(FALSE), not null
# geom           :geometry({:srid= geometry, 4326
```

That's come from activerecord-postgis-adapter, with redefined columns as such :

``` 
#<ActiveRecord::ConnectionAdapters::PostGIS::SpatialColumn 
  @sql_type="geometry(Geometry,4326)",
  @geo_type="Geometry",
  @geometric_type=RGeo::Feature::Geometry,
  @srid=4326,
  @limit={:srid=>4326, :type=>"geometry"}
  [...]
>
```

This fix displays them like this :

```
# name           :string(3)
# active         :boolean          default(FALSE), not null
# geometry       :geometry         geometry, 4326
```

Another possibility would have been to display them as below, but it involves a lot of extra-spaces for other columns.

```
# name           :string(3)
# active         :boolean                   default(FALSE), not null
# geometry       :geometry(Geometry, 4326)
```

Changed references to `--additional_file_patterns` to be `--additional-file-patterns` to make it consistent with other flags.

Adds tests for `.include_routes?`, `.include_models?`, `.skip_on_migration?`. Also moves the `TRUE_RE` under the `Annotate::Constants` namespace.

Prior to this change, `Annotate.include_models?` returned the inverse of `Annotate.include_routes?`. This made it so annotating models and routes was not possible to do together.

This PR adds an explicit `--models` flag and also adds it the option to `lib/generators/annotate/templates/auto_annotate_models.rake` with the default being set to `false`. 

Fixes #563 and undoes the bug introduced in #485.

In looking into #563, I realized there are gaps in test coverage. For example, `bin/annotate` doesn't have any tests. 

Tidying the spec directory to make it easier to add tests in future work.