Merge pull request #110 from bvssvni/master

Pointing back to rust-sdl2
Merge pull request #111 from bvssvni/master

Pointing sdl2 to crates.io
Update README.md

Added instructions to add dependencies.  These are nice to have in the readme plainly visible since they break dependent when they are changed.
Merge pull request #112 from admazzola/patch-1

Update README.md
Removed `rustc/cargo -v` from .travis.yml

See https://github.com/PistonDevelopers/piston/issues/794