progs/demos: added new demo "fbo_firecube"

progs/glsl: added new demo "pointcoord"

src/gallium/drivers/cell/spu: added the g3d_spu executable, a Cell SPU
executable file, which seems to be occasionally built as part of the
cell driver

src/glu/sgi: added "exptmp", a byproduct of the "mklib" process that
sometimes gets deleted and sometimes not.