Added assimp library.
Add project support for assimp on mac
Fix assimp on Linux
Added note about content
Removed unused parameter
Adjusting assimp project
More tweaks
Updated to the newest version of pegasus.
Updated file_to_buffer and related functions to accept size_t instead of plain int.
Override NSApplication on MacOSX to fix an issue with KeyUp handling.
Cleanup event xwl callback