TTT: add some hooks

Requested hooks for when a player has bought a thing, and when a player
found DNA.
Skin & bodygroup settings for medics
Refugee arms
Linux hates folder names starting with a number
Update README.md
Update README.md
Chell player model
Skeleton player model (rattle me bones)
Skeleton menu anim (rattle your bones)
Fists changes

Removed unnecessary code and fixed issue with Silverlans SNPC addons
Chell arms
Look in maps/thumb/ for thumbnails
The no map icon icon is in maps/thumbs/ now
The no map icon icon is in maps/thumb/ now
Merge pull request #442 from robotboy655/patch-2

Fists changes
Fixed the Chell player model overriding the Portal 1 Chell ragdoll
Show the branch on the menu
Fixed updates URL
Send BRANCH to menu HTML
Show formatted version string on the menu instead of the number
A faster way to load map icons