Changes for the New feature test for credential encryption CRAM-MD5 or PLAIN

Change-Id: Ic777b04e87670f0a9d967b4a439fea205b129e97
Reviewed-on: http://review.couchbase.org/32588
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Tested-by: Deepti Dawar <deepti.dawar@globallogic.com>