Update README.md
Fixed wrong method call in TiledTextureRegion.setTextureX (thx to GitHubDemon).
Added Apache v2 LICENSE.md file.
Update ManhattanHeuristic.java

The algorithm was incorrect. It works as expected now.
Updated .gitignore for future Android Studio support.
Added crashlytics xml file to gitignore.
Merge pull request #218 from ebbybeh/patch-1

Fixed a bug in ManhattanHeuristic.
Merge pull request #1 from nicolasgramlich/GLES2

Merged to latest version