+ Move ajax requests to promises base
+ Define constants for API URLs
+ Handle errors based on network connections problems as well as server-side logic errors
+ Generalize code so it can be used by modules & submodules simultaneously
+ Update name of module after 1 second, not waiting for focus out event

Server had been returning number of affected rows minus one: either 0, or -1. This value is converted to bool (res == 0), and js displayed an error.

+ new API methods
+ some code refactoring

+ Functions create, edit and exists in the discipline model
+ Redirect time switched to 500 ms

This reverts commit 56686b39.

Добавление/Удаление бонуса