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remove #if __linux__

destroy app_ instance on guiDestroy

Heat map utility functions.

Added normalize function to heat map

Make atlas have a max dimension of 16384

Remove extra vector declaration.

Fixing overlap order bugs.

Updating mac/linux for new functions and another close request.

Finishing close requested and moving some callbacks around

Setting up closed requested callback.

Tweaking some flag setting and double checking a dangling pointer.

Reset redrawing_ flag when a child is removed from hierarchy

Added test for redrawing_ flag reset.

Make sure text quad is big enough for floating point offsets