Enhance ReplicationTest with some checks from iOS ReplicationAPITests.  currently fails because there is no "mode" property yet.
Rename getMode() -> getStatus()
bump minSdkVersion to 9 to fix IDE warnings
While testing was seeing invalid case where asyncTaskCount was -1.  Add assert() as in iOS code.
Only call asyncTaskFinished if !isContinuous.  (attempting to get testRunReplicationWithError() working the same as it does on iOS)
return valid value for getStatus() rather than unsupported exception.  Still more work to do regarding status
track and propagate change tracker error to puller.
replications default to continuous == false now.
add testRunReplicationWithError() which now passes.  (but other tests are currently failing)
Add another mechanism to wait for replication to finish - uses polling, more like iOS test.
add testGoOffline() to check status after going offline.
implement goOffline(), testGoOffline() now passes.
Update status whenever notifying change listeners
Add restart() method
Move ChangeTrackerTest to replicator package.  Add docIds property, unused.
Refactor ChangeTracker to be in the replicator package
add testChangeTrackerWithDocsIds() and modify impl so test passes.
Propagate docIds from replication -> change tracker
add get/set channels + test case
enhance testChannels to deal with setting to null.