Create RoutingManager that is separate from TopologyManger. It hooks into TopologyManager via new ITopologyManagerBackend, butmakes it much more obvious that the TopologyManger and TopologyInstance is responsible for much of the routing. Before this change, the actual 'routing' and 'path-finding' implementation location wasn't very clear.

compute() has been optimized and all old code is gone. We no longer need to compute trees for each cluster. Furthermore, the computation of broadcast ports has been streamlined. Other routing/topology refactoring has been done as well.

Transferred over all of the Yen's algorithm additions. This includes getRoutes(). Some additions may have been missed.

* Eliminated (new) warnings
* Fixed indentation
* Removed excess blank lines
* Improved some varable names
* Removed (unneeded) commented-out code
* Fixed up comments
* Added @Override annotations

Updated Firewall.java so that addRule and deleteRule and enableFirewall announce that a rule is being changed in the firewall. Then the IRoutingDecisionChangedListener shall alert Forwarding to update the flowtable accordingly.  None of this is tested and the TopologyManager needs to be fixed.  I might even want to move the change out of TopologyManager altogether since RoutingDecisionChange doesn't concern it.

This reverts commit 4ae94669.

Refactored structure of core components to work with openflowj-loxi.
Presently refactoring Routing, Firewall, Forwarding, DeviceManager,
LinkDiscovery, Topology, and LearningSwitch.
Hub has been refactored.

floodlight changes to accommodate future multi-route implementation - add cookie field to all getRoute() methods

- Add getRoutes() to IRoutingService, dummy getRoutes() to TopologyManager - update Link to be comparable/sortable - add routeCount to Route - add cookie to RouteId - make NodeDist protected

Updates to BroadcastTree data structure; Renaming of IRoutingEngineService to IRoutingService; Updates to signatures of IRoutingService interface methods.