Feature: Auto-Completion in Source Code

+ allow flags for exercises

db/migrate/20160907123009_add_allow_auto_completion_to_exercises.rb

@@ -0,0 +1,5 @@
+class AddAllowAutoCompletionToExercises < ActiveRecord::Migration
+  def change
+    add_column :exercises, :allow_auto_completion, :boolean, default: false
+  end
+end