Improve README.md

README.md

@@ -10,6 +10,7 @@ Add this line to your application's Gemfile:
 
 ```ruby
 gem 'whaleback'
+
 ```
 
 And then execute:
@@ -22,6 +23,10 @@ Or install it yourself as:
 
 ## Usage
 
+Copy migrations to your project
+
+    $ rails g whaleback:migrations
+
 TODO: Write usage instructions here
 
 ## Development