Lightweight Java Game Library Code

Linux: Hardened getAvailableDisplayModes so that it won't be confused by a changing number of display modes while it is executing

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Added more debug output to linux

Added java debug output to linux display.c

Linux: Fixed problem with updating screen dimension globals

Linux: reset/restore gamma settings on activate/deactivate

Converted native code from C++ (.cpp files) to C (.c files), thus avoiding an annoying dependency on the standard C++ library on Linux. We weren't using any particular C++ features anyway.