Fix Entities.waitForServiceUp to avoid NPE

- Never return null for repeater’s `until`; always return TRUE or FALSE.
  Otherwise it will NPE.
Tidy EntityTransientCopyInternal
BrooklynLauncherTest: use LocalManagementContextForTests

- speeds up the test slightly
DynamicMultiGroup: fix+test removing empty bucket

- Previously gave ConcurrentModificationException when removing,
  iterating over Sets.difference, because that set is a live-view
  rather than a copy.
This closes #336
Adds RebindOptions for RebindTestUtils etc

- Changes RebindTestFixture default to not checkSerializable.
- Deprecates crazy number of overloaded methods
Configure attribute for storing PropertiesReloadListener for later removal
Document purpose of attribute for reload listener
Added Beta annotation
This closes #337

* github/pr/337:
  Added Beta annotation
  Document purpose of attribute for reload listener
  Configure attribute for storing PropertiesReloadListener for later removal
This closes #309