added try/catch blocks around texture upload in AssetManager's 'onRestore' methods

If the context is lost again while the previous loss is still being restored, you ran into "object disposed" exceptions. This way, nothing bad will happen.
fixed internal render texture projection matrix for usage with RectangleTextures
Allow for json encoded arrays.
Merge pull request #370 from rickms/master

AssetManager now supports JSON array encoding.
Merge remote-tracking branch 'refs/remotes/upstream/master'
added support for custom texture formats (closes #153, #368)
using texture format BGRA_COMPRESSED for text field TTF rendering

Requires only 50% of the texture memory, quality changes virtually invisible.
made previous text field change backwards compatible
for consistency, only restoring 'fromColor' texture when context loss handling is activated (closes #371)
small refactoring of 'handleLostContext' checks in texture classes
removed erroneous dispose (caused failure on context loss)
forcing POT for runtime-compressed textures
Using modified mouse cursor handling which does not require onTouch listeners on each object which require different mouse cursor. Multitap part of code used only if specified in compile settings.
Merge remote-tracking branch 'refs/remotes/upstream/master'