Refactoring of linkstate module.

- removed ByteList
- refactor to use Multimap to allow for multiple keys in map
- simplified AdjRIBsIn class
- use UnsignedInteger for casting back longs

Change-Id: Iebdf4081bad909fd861d8a10b8b7286f70962038
Signed-off-by: Dana Kutenicsova <dkutenic@cisco.com>
Signed-off-by: Robert Varga <rovarga@cisco.com>