Test stream end upr api

1. Send stream end command when no stream exists

• Send the stream end command and expect to be disconnected

2. Send stream end command to producer

• Open a producer connection
• Send a stream end command and expect to be disconnected

3. Send a stream end command for an invalid stream

• Open a consumer connection
• Send a stream end command and expect success

4. Send a stream end command to a valid stream

• Open a consumer connection
• Send an add stream request for some vbucket
• Check the stats to make sure the connection exists and is not in dead state
• Send a stream end command for the opened stream and expect success
• Check the stats to make sure the connection is in dead state

One thing to note here is that I am note sure whether or not the stream end command returns a response or if it is a silent command. If it is silent then just don't wait for a response and poll the stats for a reasonable amount of time to try to figure out if the stream end message was processed.