Fix replicated requests on clusters with less than Replicas+1 nodes

  Modify one of the UTests so that it would catch the bug (the callback
  wasn't called on a SET request if Replicas+1 > nbOfNodes)

Change-Id: I2b49de8911dbcf8f8d8d10f0bff37ea3636179e4
Jira: STO-877
Refactor key type from string to byte[]

Change-Id: Icf4f1d38b7830a7fb3d37a3233ae1cae967576e3
Cleanup, move to Encoding.UTF8

Change-Id: I1a822f208ed4a4a4382c0c44f742f511722cbad7
Work on supporting CouchBase

Change-Id: I75327184724c3355e596bad21bdbdd057e53d616
Add warmup method on client

This will allow to establish one connection to each node in advance

Change-Id: I8dc777dba8e0160c3411e6de20d41a1d3cc5e2c3