Make sure KEWatcher only kills child Resque Processes

Origionally, we were killing the parent Resque Process, not the child which actually does the work.

Instead of keeping track of this in internal state, we just use ps and friends to make a list of
offending children processes which have been running longer than they should be.
Merge pull request #2 from seomoz/fix-kill-children

Make sure KEWatcher only kills child Resque Processes