More reorganisation to the code

Updated the "scriptfiles" folder, this now contains all the updated
files required to run the server and plugins. As well as readmes for
various files and their structures.

Moved all player variables to the Player.pwn script.

Renamed the folder "/scripts/SSS/" to "/scripts/Core".

Moved all files containing mainly just data that could possibly be
customised for different versions of the game.

Renamed "SanAndreas" map data folder to "sa", the compiler didn't accept
the name and ignored the code due to an internal compiler bug.

Moved some more files around to different folders, generally just
logical decisions relating to what the script actually does.

These updates attempt to make the overall server code more flexible so
it's easier to add new maps or tweak data values (such as loot spawn
chances, spawn points, vehicle data and weapon damages)