Updates to DeviceManagerImplTest corresponding to changes in attachment point computation using topology last changed time.

When sending LLDPs and BDDPs from all the switches, send LLDPs first and then BDDPs. This would enable direct links to be detected first and reduced instability.

Fix build issues caused by the introduction of PacketFactory. Now the net.floodlightcontroller.core.test.* files will not try to be run as jUnit tests.

topology keeps a list of applied link updates. topologyAware modules can query updated links after getting topologyChanged event

Update to attachment point flapping logic.  Use active time instead of last seen to order the entities.  Corresponding changes to unit tests.

1 - Unit tests
2 - REST API
3 - Handle multicast/broadcast