Ability to rename wp-admin and wp-login in wp-config.php

[nabtron]

I have been dealing with multiple requests from users who get constant bruteforce hits on wp-admin and wp-login.php file.

One solution is to make them renameable by removing hard coded values from the codebase and replace with e.g. ADMINPATH and LOGINPATH (like ABSPATH) which may be editable in wp-config.php.