Fix build infrastructure to work with tests

- Move `Rcm` and `Test` under `src`.
- Add a `src/Makefile.am` that knows how to build Haskell.
- Update the test helper to have `src` in its path.
- Re-enable the `bin` directory, but disable `bin/lsrc`.

The tests fail, because the output is still debug output. This is
expected.