Complete issue #118

Port adding TODO and fixing log typos in Pusher class
Merge pull request #135 from couchbaselabs/issue-118

Complete issue #118
Complete issue #119

Minor enhancements to logging messages in Replication class
Merge pull request #136 from couchbaselabs/issue-119

Complete issue #119
Fix issue #98

- Change to notify ChangeTrackerReceivedChange event synchronously with its own thread
- rename runningMutex to stopMutex
- improve log messaging
Merge pull request #137 from couchbaselabs/fix-issue-98

Fix issue #98
Fix replication auth

Set credentials to the HttpClient if available. This code is somehow missing probably due to the merge process.
Merge pull request #138 from couchbaselabs/fix-replication-auth

Fix replication auth
Complete issue #118

- Refactor Replication.GoOffline() and GoOnline() to operate async within Manager.WorkExecutor.
- Fix Replication.TestGoOffline().
- Pusher.BeginReplication no longer called AsyncTaskStarted() according to the upstream iOS code.
- Puller.GoOffline() is set to an internal method.
- Improve some logging messages.
Merge pull request #139 from couchbaselabs/issue-117

Complete issue #118
Merge branch 'master' of https://github.com/jonlipsky/couchbase-lite-net
More fixes.