Adds cyrus-sasl-plain note for SASL config to user guide.
1122987 - Adds troubleshooting note around Qpid scalability limits
Merge pull request #1213 from bmbouter/1122987

1122987 - Adds troubleshooting note around Qpid scalability limits
Merge pull request #1204 from bmbouter/1099954

1099954 - Adds cyrus-sasl-plain note for SASL config to user guide
Merge branch 'tmp' into 2.5-testing
Merge branch '2.5-testing' into 2.5-dev