Tests for Hierarchical Select!

tests directory: http://drupal.org/cvs?commit=181602
hook_simpletest() implementation for HS: http://drupal.org/cvs?commit=181606

Now onto the actual work: writing the tests! Here's an initial set of tests. I'm just posting these for reference and as a means of showing progress, but it's nowhere near finished. It might need some further tweaking to reduce the LOC needed though.

Thanks to litrik for feedback on how to make the tests more concise and how to make it cover enough edge cases. Feedback is welcomed.