Changes the CDTReplicator.state property to be equal to CDTReplicatorSta...


If the replication was stopped via a call to CDTReplicator -stop, the status should be 'Stopped'. Otherwise, if
the replication stops on its own because it completes, the status is set to CDTReplicatorStatusComplete.

Changes the CDTReplicator code to clarify the object's state,
progress (changesTotal and changesProcessed), and messages sent to delegates
during start, stop and updates to the replicator.

Adds tests in ReplicationAcceptance using a delegate to stop replication
immediately after starting.
This method should return YES or NO and the test should call the STFail macro rather than this method, otherwise it's difficult to follow test logic if checks are hidden outside the test method. In particular, it makes the method less reusable because it doesn't allow the test to only fail if the count is the same rather than differing.

The name of this method is also not very clear, it's not understandable what the parameters are from the name. Perhaps `hasDatastore:fewerDocumentsThanDatabase:`: looking at `testPushStateAfterStopping`, if the local datastore has more documents the test calling should fail.