Update 01-cheat-sheet.html.md

Fixing broken links to FlxSprite and FlxState documentation in the cheat sheet
Merge pull request #82 from MegaLeon/patch-1

Update 01-cheat-sheet.html.md
Merge branch 'master' of https://github.com/HaxeFlixel/flixel-docs into flixel-docs/Tutorial
Finished the tutorial!