Win32: Handle context-dependent wgl extensions
Linux: Handle different GLX capabilities on different screens
Win32: Compile fix
Removed unsued JNIEnv parameter from extgl_QueryExtension
Linux: Fixed glx
Moved platform specific stuff from extgl.c into platform directories
Typo fix
Clean out commented code
Mac OS X port of the refactoring. Linux and Win32 fixes.
Removed redundant include from awt_tools.h
