revert b34229cb6b9f1fc2229b8b2f894166dba3964fa7
Initial support for anti-stampede callbacks in Execution Filter, refs #744
More stampede protection callback work: also trigger started callback when readCache() failed, and only trigger finished callback when something was written (otherwise the second call which initially works on stale data kills the flag right away!), refs #744
Fixed #746: Actions that return no View are never cached.
merge fc2817eeb160bfaf67319bd9af8e8bbf77fc727f...570714771e18f5969d259ecbb592c2be70bf8ee5 from 0.11