Added physfs-stream as submodule
Updated .gitignore to allow the physfs-stream folder in contrib
Removed squirrel so it can be made a submodule
Updated .gitignore for the squirrel submodule
Updated it again...
Added Squirrel as a submodule
Removed SFML from .gitignore
Added sfml as submodule
Added sfml as submodule, updated folder
Updated SFML .gitignore
Merge pull request #11 from zackthehuman/master

Added physfs, physfs-stream, and sfml as submodules