add test to stream requests from the same vbucket

Added a test that streams request for a vbucket to read up to seq 100. Then sends another
stream request for the same vbucket.  Expect a EXISTS error and upr stats
should refer to initial created stream.
Remove an op if any message from a stream contains an error
Properly parse the extensible meta data length field
Allow stream requests to properly parse the failover log
Refactor code that checks for unexpected opaque
Add a unit test for stream request with too big of a start seqno
Add unit test when stream req contains start seqno > end seqno
Add a unit test for a stream request with an invalid vbucket
Add a unit test to create a stream on a non-upr connection
Add a unit test to create a stream request to a consumer connection
Add stop and start persistence commands
Add the ability to create and delete buckets

This allows us to run all tests against couchbase server
Stop persistence before streaming test cases
Fix the exp testcase suite
Add test to create a stream request that does backfill/memory
Fix broken mcd tests
Add two unit tests for incremental streaming
Add test to send multiple stream requests for different vbuckets