Сode refactoring. Created the necessary interfaces. Classes and
interfaces are posted on the corresponding packages
Started porting custom logic from server to the client side. Foundation
framework was included to client side application.
The logic of the user interface is moved to the client side
Small refactoring of client javascript
Changed the logic of formation and processing of user registration data
Small refactoring of client side javascript.
Created separate private class in GameFrontend for handle login requests
and build user data response.
Made refactoring of the frontend to optimize the processing of user
registration. Excluded the username validation
Minor code refactoring that is responsible for user registration. Now a
request for user registration is only possible when specifying the path
'/login' in url.