Added a VirtualViewport to help with keeping the aspect ratio and
handling a fixed viewport.
Merge remote-tracking branch 'upstream/master'
Added viewports with tests.
Removed the old VirtualViewport utility.
Added StaticViewport and changed the viewport architecture in total
Merge branch 'master' of https://github.com/libgdx/libgdx
fixed gradle template to use latest robovm gradle plugin
IsometricMapRenderer with improved culling
IsometricMapRenderer with improved culling
Merge pull request #1504 from nooone/master

Viewports
Button should still fire the change listener when disabled and checked state is changed programmatically.
It appears sorting based on y up/down is not necessary.

It gives incorrect results with clockwise, colinear points.
Merge branch 'origin/master'
Merge pull request #1503 from dajos7/master

IsometricMapRenderer with improved culling
Avoid resize being called twice at app start, LWJGL.

Display.wasResized() returns true the first time through the game loop.
Refactoring for viewports.

#1504
Merge branch 'origin/master'
Renamed viewports.
Bit fancier viewports using Scaling.

Kept the Fit/Fill/StretchViewport classes so the API is nicer to use.
Javadocs and cleanup.