Port resource watcher test to async core

 * get resource watcher test to work with the new async core
 * extract duplicated test code into intent-revealing test methods
 * make leaky process safer by constraining it to reasonable limit, in
   order to prevent freezing developer's machine when working on these
   tests
Update list of tests in need for love
Merge pull request #6 from amarandon/async_experiment

Port resource watcher test to async core