NCBC-493: Implement Replica Read Capability

Change-Id: Ie1261b149864a8f87545814d10b390141cba5f6d

Conflicts:
	Src/Couchbase.Tests/Core/Buckets/CouchbaseBucketTests.cs
	Src/Couchbase/Couchbase.csproj
	Src/Couchbase/IO/Operations/OperationCode.cs
Change-Id: I9ab0dcf1a3dfde832fd55687d1e06958246b2a2e
Reviewed-on: http://review.couchbase.org/43437
Reviewed-by: Jeffry Morris <jeffrymorris@gmail.com>
Tested-by: Jeffry Morris <jeffrymorris@gmail.com>