Tasks stop on unmanaged

stop tasks when entities are unmanaged, and better bookkeeping for scheduled tasks.
(also fixes eclipse IDE problems caused by checkstyle.)
This particular instance I just fixed the `runRequiringTrue` bit but elsewhere I added some `Repeater` calls.  It's just such a nice API :) but agree `Asserts.eventually` is more appropriate and allows external control of timings.

(One minor point, if I'm *debugging* tests, it's nice to have control of timings, so perhaps a `Asserts.DEFAULT_EVENTUALLY_TIMEOUT` field would help.)