Merge branch 'szzh' into develop

app/api/mobile/api.rb

@@ -1,5 +1,11 @@
 module Mobile
   require_relative 'middleware/error_handler'
+  require_relative 'apis/auth'
+  require_relative 'apis/users'
+  require_relative 'apis/courses'
+  require_relative 'apis/watches'
+  require_relative 'apis/upgrade'
+  require_relative 'apis/homeworks'
   class API < Grape::API
     version 'v1', using: :path
     format :json