Adds ServiceFailureDetector stabilisation delay
Fix CompoundTaskExecutionTest.testParallelTaskFailsWhenIntermediateTaskThrowsException

- failed in jenkins; fixed race in test
Fix DynamicSequentialTaskTest.testCancelled
rebind's loadMemento: guard against NPE
PR #1346: incorporate review comments

- ParallelTask.get() waits for all sub-tasks to complete before 
  returning, even if one fails
Merge pull request #1346 from aledsage/fix/various-20140430

Fix/various 20140430