* The old way: a user hook in Setup.hs
* The new way: specify it in gf.cabal
* The test suite is now called gf-tests, and it runs testsuite/run.hs.
* You can run it manually with 'runhaskell testsuite/run.hs'. It also runs,
together with rgl-tests, when you do 'cabal test'
* Currently only 9 of 34 tests pass. Many failures have silly causes:
- Error messages that look slightly different
- Same output but in a different order
- Absolute paths in output
