If an attachment point port from packet-in does not replace already known attachment point, put it in oldAP list only if it was picked up from oldAP list.  Otherwise, ignore the attachment point.

Bug fix: when an attachment point from packet-in (newAP) does not replace the already known attachment point (oldAP), then we need to put newAP in the oldAPlist for possibly flagging it as duplicate in the future.  Earlier, we were adding the already known attachment point in the list.

Clear out oldAPs whenever updateAttachmentPoint() is called as it is triggered due to topologyChange and device reclassification.

Update to attachment point comptuation to flag devices flapping between two switch ports.  Enable duplicate mac unit tests.

Update attachmentpoint whenever topologyChanged() notification is received.  It is not necessary to process every event; just one update call per topologyChanged() should take care of fixing all attachment point changes.

Updates to attachment point learning and udpating.  DeviceManager listens to topologyChanged() events.  Whenever a port goes down or a switch is removed, attachment points are updated.  Cleanup of link discovery manager updates; cleanup also includes port up/down switch update/removed messages.

Rewrite of attachment point logic.  Attachmetn points are maintained independent of entities.  Update test cases.  Duplicate Mac test is disabled for the time being.

Bug fix: prevCluster assignment is changed to reflect the L2 domain ID of the prev entity.  It was possible for cur and prev to be swapped when duplicate attachment points were detected, where the prevCluster could have the wrong assignment.

BSC-2116

* Fixed couple of bugs in Device.getIPv4Addresses().
* Add more debugging output to DeviceManagerImpl

* implement findDestDeviveByEntity()
* findDevice() and findDestDevice() will now throw an exception of the
  supplied fields are not sufficient for the lookup
* test and comment polishing
* reorganizing testing code

[BSC-1838]

* IEntityClassifier only returns a single entity class per entity and all
  entities of a device must belong to the same entity class. Semantics for
  multiple classes was unclear.

* IEntityClassifier is now an IFloodlightService to have a cleaner way of
  setting the classifier to use (the classifier needs to be set before
  DeviceManager.startUp() is called).

[BSC-1838]

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

DeviceManager update to take into account that previous attachment belongs to non-broadcast domain attachment point.
Adding an interface to ITopologyService that indicates if tunnels are enabled for traffic between two hosts.

Update device manager to handle consistent attachment points to properly handle duplicate device flagging.

Add a debug REST API to get raw device entities.  Fix attachment point blocking code and make it appear in the REST output