Revision 1494306

QPID-4745: Alternative port allocation for tests, instead of 'qpidd --port=0'

qpidd-p0 script binds a new port to a socket using bind(0), and then
execs qpidd using the --socket-fd option to pass the socket to qpidd.

It is intended to replace
  /path/to/qpidd --port 0 <args...>
with
  qpidd-p0 /path/to/qpidd <args...>

Most tests do not yet use qpidd-p0, they will be updated in a future commit.

Changes:
- Added qpidd-p0
- Fixed qpidd port printing logic: print port only if --port=0, regardless of --transport.