QPID-4865: HA Update documents for queue replication

- Added information needed to use HA queue replication as a replacement for
  old async queue state replication.
- Updated links in README-HA.txt to point to (as yet non-existent) 0.22 documentation.
- Removed lingering traces of old broker.

git-svn-id: https://svn.apache.org/repos/asf/qpid/branches/0.22@1484867 13f79535-47bb-0310-9956-ffa450edef68