- Fetcher Check for ErrorCode.NoError for returning messages in MessageStream

- Fetcher send out PartitionStateChange when receiving partition with ErrorCode != NoError
- TopicPartition better logging messages\
- Add custom ErrorCode.FetcherException for failed fetchers
- Router better logging
- Router subscribe to error feed on Fetcher.ReceivedMessages and remove fetcher from _activeFetchers
- Tests - create new VagrantBrokerUtil with all vagrant helper functions for testing
- Tests - RestartBrokers checks if broker is up before issuing Start command