Removed Observer pattern from Memebrship & Consistent hashing.

-RepairData.toString()
-ByteArrayWrapper maintains key and raw_key. Choice can be made to store
one key or two.

-ConsistentHashing maintains a List of RepairData, i.e. repair work in
form that handler can begin processing.
Merge branch 'GossipObserver' of https://github.com/VWJF/eece411P2.git into GossipObserver