-Added new screen resizing options, stretch_2d is removed, new much more flexible ones.
-Fixed bug in viewport (can create more instances in 3d-in-2d demo now)
-Can set android permissions and screen sizes manually in the export settings
-Changed export templates extension to .tpz (too many people unzipped the manually..)
-File dialog now ensures that the proper extension is used (will not allow to save without it)
-Fixed bug that made collision exceptions not work in 2D
