This is a substantial reorganization, This particular commit enables:
- building the progs for unices platforms
- glew is now built as a shared library (it is the default, and it is
inconvenient and pointless to shift away from that default)
- all progs get built by default
This is pretty ugly as the original framework assumed you'd set
a single window size at startup and keep it throughout, but for
swapbuffers you want to test the rate at various window sizes.
With luck a nicer solution can be found, but this at least lays out
a marker.
