redo rooms page

db/migrate/20180504131648_create_users.rb

@@ -1,6 +1,7 @@
 class CreateUsers < ActiveRecord::Migration[5.0]
   def change
     create_table :users do |t|
+      t.belongs_to :room, index: true
       t.string :provider
       t.string :uid
       t.string :name