Reimplement mobile-sync as a core module

The code in Qpid Dispatch Router currently does mobile address synchronization between routers in the Python router module. A large mobile address update can cause delays in processing management requests and link-state topology maintenance.

To improve performance when there are large numbers of addresses in a network, move mobile address synchronization into a core module where it can use and share the same address table that is used by the router core for making high speed routing decisions. In the process, it will leave the python modules alone to process management requests and topology maintenance uninterrupted.

For a more detailed description, see https://issues.apache.org/jira/browse/DISPATCH-1532