[Piglit] Support for more tests to run with -fbo

[Chris Forbes]

This is the first batch of patches which get rid of some
stumbling-blocks for running tests with -fbo.

Highlights:
- gSwapBuffers -> piglit_present_results
- glutKeyboardFunc never in -auto
- glutReshapeFunc -> piglit_*_projection
- some glReadPixels -> probes
- actual bugfix (fp-kil assumed `1` was an unused name)