홍길동 / onos

  to get the Ip4Address and Ip6Address view of the IpAddress.

* Added methods IpPrefix.getIp4Prefix() and IpPrefix.getIp6Prefix()
  to get the Ip4Prefix and Ip6Prefix view of the IpPrefix.

Added the corresponding unit tests as well.

Change-Id: Iaa462b142d3cb65be4715f38a1b8188c273dd395

No functional changes.

and the corresponding unit tests.

* Reimplemented classes Ip4Address and Ip6Address by inheriting from
  class IpAddress
* Reimplemented classes Ip4Prefix and Ip6Prefix by inheriting from
  class IpPrefix
* Reimplemented the unit tests Ip4AddressTest and Ip6AddressTest to
  match the corresponding IpAddressTest unit tests
* Reimplemented the unit tests Ip4PrefixTest and Ip6PrefixTest to
  match the corresponding IpPrefixTest unit tests
* Minor refactoring/cleanup of classes IpAddress and IpPrefix

Change-Id: Ie4bb5b5f53fcf0036f0d48bab3cdcd88ced24fc4

Change-Id: If3d9777583a38d911b19bb1bc50212ccb621918a

Change-Id: Ie391feb6ef0fa79ea859e89e8a2fd51d59f03cea

Using sample views for now.
Still WIP.

Change-Id: I3c85f761386b05ab40173b944966d4448ba8d033

Change-Id: If9b50a8e5db29e4bae2c93b51f34c5e043563094

Change-Id: I040eee94d2eb2622b32fbe8dbf06d81b54765065

Change-Id: I8741c41a74dba3b816a838aa1db1588be7f9816a

Change-Id: Ia333fb4f9c4af3642482f626e5660e0339d13995

Change-Id: I5f0994ebbb46bb7bfe5926a27923f0971b58729a

Change-Id: I5c1f8aebaadab07a7675cbe5467b07b24bf768e1

Change-Id: If0d838d02690ad4bb581152b40d366c124826634

Change-Id: I3b4fc2d99f42b2413a535fb411b9c19bdd186ad8

Change-Id: I7965684f9f9c67c65c7e114f061afef04dac4c3a

Change-Id: I3598fceb8f30c501eafcfb54d75b2e4f48d8537b

Change-Id: I5bf0fc76ffd04d5a1165d24e82eedd7993ec95be

Change-Id: Iaf2b47ce7cfad7fcd5b57c8ec79e0d3e6e66ca73

Conflicts:
	utils/misc/src/main/java/org/onlab/graph/MutableAdjacencyListsGraph.java

Change-Id: I6b836c844e460cc8ced983c7d4eefadf3fc839dc

Change-Id: Icd3b2e483b15486251ac1cca107478a012d1a3e7

Change-Id: Idd830437efb3766e82f8c6601ddd5ea7b33bf108

Conflicts:
	core/store/dist/src/main/java/org/onlab/onos/store/mastership/impl/DistributedMastershipStore.java

Change-Id: I736ec55c6211a505d6cf43ab22e1197fdb86ecf3

Change-Id: Ic0a36391ff22247d20d3e2b185c4d867a4e81780

a new set of IpPrefix unit tests.

Also, fix few nits in IpAddress and IpAddressTest