Here is a brief explanation on how to sync Mesa in trunk base.

Current version is 8.0.4

- SOURCE FILES :
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All unnecessary files and directories where removed from the tree, as it's already a huge piece of code.

 - build tools (bin, configs, scons, src/gallium/tools) were removed, as we don't use it.
 - documentation (docs, src/gallium/docs, doxygen) were removed. If you want to contribute to libMesa, you'd better use their build system, not our adapted one
 - tests and testing tools were removed (test, src/gallium/tests, src/gallium/tools)
 - egl functionality (src/egl) is useless to us and were removed.
 - gbm functionality (src/gbm) is useless to us and were removed.
 - getopt implementation (src/getopt, for MSVC compatibility) is useless to us, we already have one
 - glx (src/glx) functionality is useless to us and were removed.
 - src/gallium
   - All gallium drivers (src/gallium/driver) where deleted, except for the softpipe  one.
   - All gallium state trackers (src/gallium/state_trackers) were removed, except for the wgl one
   - All gallium targets (src/gallium/targets) were removed, except for the libgl-gdi one.
   - All gallium window system backends (src/gallium/winsys) were removed, except for the gdi one (sw/gdi)
 - src/mapi
   - only mapi and glapi directories were relevant and kept
 - src/mesa
   - All MESA drivers where deleted (src/mesa/drivers), except for the "common" part and osmesa (off-screen mesa) library.
   - Architecture specifics were removed. x86 and x86_64 might be restored in future
 - src/glu where kept and will be used for the glu32 dll implementation


- GENERATED FILES:
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libMesa build system generates source files (using scons).
They were taken from an out-of-source build an put in the "generated" directory, using the same 
directory structure for the sake of ease of maintainability.


- CMAKELISTS FILES:
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Those files were written using the Sconscript and source list files as reference. I think that diff-ing them between two 
versions would permit to easily update the cmake configuration files.
