Add difficulty levels

db/migrate/20140212172244_create_difficulty_levels.rb

@@ -0,0 +1,12 @@
+class CreateDifficultyLevels < ActiveRecord::Migration
+  def change
+    create_table :difficulty_levels do |t|
+      t.references :conference
+      t.string :title
+      t.text :description
+      t.string :color, :default => "#ffffff"
+
+      t.timestamps
+    end
+  end
+end