[CX] DcpBucketState.toString() needs to be more compact

DcpBucketState.toString() is logged every time DCP stream is resumed at WARNING level. This outputs 1024 lines of status e.g.

2017-03-11T18:37:45.755Z WARN CBAS.adapter.CouchbaseConnectorFactory [HttpExecutor(port:8095)-2] Resuming DCP streaming from Number of Partitions = 1024
vbid = 0, uuid = 0, seq = 0
vbid = 1, uuid = 0, seq = 0
...
vbid = 1022, uuid = 0, seq = 0
vbid = 1023, uuid = 0, seq = 0

The toString() ends with a newline, which also should be removed.