Fix issue of duplicate creation for connections in impl_qpid

Within __init__ of Class Connection, self.connection_create and
reconnect() will both construct a new connection object. Need to fix
it.

Change-Id: I6e3183d36d11995970fb8dce45240f804ec52ab4
Closes-Bug: #1330364
Merge "Fix issue of duplicate creation for connections in impl_qpid"