Revert "Merge remote-tracking branch 'upstream/master'"

This reverts commit 112b3dd22605ccf2db257dbf92e10b1ef4e73aa3, reversing
changes made to ba710af27a4aedb68e832258447193631cb22cc6.
Revert "Revert "Merge remote-tracking branch 'upstream/master'""

This reverts commit 770531b77e54e024cc3f82665d2cae599f8d9df3.
Merge branch 'master' of https://github.com/tamdinh/libgdx
Merge branch 'master' of https://github.com/tamdinh/libgdx
Add DataOutput class to gdx.gwt.xml.