Gang Garrison Builder 2

Adds a bunch of stuff including:
* Dynamic gamemode and entity loading (making it really easy for plugins to add stuff).
* Built in garrison builder with the ability to instantly toggle between playtesting and building.
* New map saving format that allows custom properties such as scaling and more (see moveboxes and medcabs)
* Fixes moveboxes speeding up faster in 60 fps mode (while also adding a speed property)
* Ajfs GGON
* Cspotcode's dll because ajf told me to.

See thread here: http://www.ganggarrison.com/forums/index.php?topic=35951.0
(the mod download there is not up to date with the repository)

Ps I didn't do A LOT of testing, but everything seems to work.
Given you're duplicating this line for each type of movebox, you might as well make `MoveBoxLeft`, -Up, -Down and -Right just be children of a parent `MoveBox` object. Actually, you could then just make the direction be a property and get rid of them as entities proper... which would be pretty cool actually, you could make it an arbitrary angle. Wouldn't that be cool? You don't have to do this, but it'd be pretty cool.