Renamed to sdl2_window

Closes https://github.com/PistonDevelopers/sdl2_game_window/issues/74
Merge pull request #75 from bvssvni/master

Renamed to sdl2_window
Renamed title to sdl2_window in README

Closes https://github.com/PistonDevelopers/sdl2_window/issues/76
Renamed WindowSDL2 to SDL2Window

Closes https://github.com/PistonDevelopers/sdl2_window/issues/77
Merge pull request #78 from bvssvni/master

Renamed WindowSDL2 to SDL2Window
Renamed SDL2Window to Sdl2Window

Closes https://github.com/PistonDevelopers/sdl2_window/issues/79
Merge pull request #80 from bvssvni/master

Renamed SDL2Window to Sdl2Window
Fixed example in README

Closes https://github.com/PistonDevelopers/sdl2_window/issues/81
Added dependency graph to README

Closes https://github.com/PistonDevelopers/sdl2_window/issues/82
Merge pull request #84 from bvssvni/master

Added dependency graph to README
Fixed missing docs warning
Merge pull request #85 from bvssvni/master

Fixed missing docs warning
Upgraded build status button for renaming

Closes https://github.com/PistonDevelopers/sdl2_window/issues/83
Upgraded to lastest piston-event
Merge pull request #86 from bvssvni/master

Upgraded to lastest piston-event
Upgraded to latest piston-event
Merge pull request #87 from bvssvni/master

Upgraded to latest piston-event
Upgraded to latest piston-event
Merge pull request #88 from bvssvni/master

Upgraded to latest piston-event
Updated to latest piston-event