Clean-up, syntax update and tweaks

[Dragonisser]

• Tweak: Max clients connected is by default 6
• Tweak: Max clients connected is read from the database table "map", specifically the column "player_limit".
• Tweak: General clean-up of warnings and errors in the code, as well as updating the syntax to SM 1.11 (like steamtools.inc)
• Fix: new players will now be added the "player" table in the database.

Dependencies are still the same