BROOKLYN-66: Fix deadlock in LocalEntityManager
Fix concurrency issue stopping cluster

- when resizing to zero, we shrink by currentSize. If someone
  concurrently stops an entity, then don’t worry that we were only
  able to stop (currentSize-1) entities. Just continue.
Fix failing ServiceReplacerTest.testSetsOnFireWhenFailToReplaceMember
Change EntityAdjuncts.findWithUniqueTag to tryFindWithUniqueTag

- Make it consistent with guava naming
Move some tests form AbstractEntityLegacyTest to EntitySpecTest
Simplify HighAvailabilityManagerSplitBrainTest
CatalogLibrariesDo: minor tidy