SSE is now unconditionally enabled any where and most of math.h is now
actually implemented. using __builtin_<func> lead to many hangs where
the builtin function would just call itself.
I don't know why I had not specified optimization level for libraries.
Only LibImage was using explicit -O3. LibImage doesn't need O3 anymore
as O2 seems to be around the same speed.
Now files are installed using the install() command instead of manually
copying files to their destinations. This allows automatic recompilation
of headers that did not work previously