Blender Git Loki

SCons updates
* Internationalization support is now available on Linux. By default this
feature is disabled. The reason is that you need to have a precompiled
version of the ftgl library for your gcc version.
To enable ftgl support you need to do the following:
- compile ftgl.
- set USE_INTERNATIONAL='true' in the config.opts file
- set the FTGL_INCLUDE and FTGL_LIBPATH to valid locations.
Freetype2 is detected automatically on your system by using pkg-config.

There was a problem with linking libraries. I took a look at how the
Makefile environment did it, and copied the mechanism. Now we're linking:
freetype, blender_ftf, ftgl and freetype. (Yes, 2x freetype).

* Minor variable cleanup.
sdl flags are now collected in one Environment() in stead of two. Adapted
all relevant platform variables accordingly.