Add room and dates to tracks

They are required only for accepted and confirmed self-organized tracks

db/migrate/20170712120556_add_room_and_dates_to_tracks.rb

@@ -0,0 +1,7 @@
+class AddRoomAndDatesToTracks < ActiveRecord::Migration
+  def change
+    add_reference :tracks, :room, index: true, foreign_key: true
+    add_column :tracks, :start_date, :date
+    add_column :tracks, :end_date, :date
+  end
+end