MB-4695 allow http://<server-name> when adding node to cluster

- implemented correct url parsing on server side

- removed host:port parsing from the client code

- unified the interface of addNode and doClusterJoin
by introducing hostname parameter for doClusterJoin
with preserving the old parameters for backward compatibility

Change-Id: I29e5cf1fc5a2b06d7d63b0b3325a5124e6d0ee21
[alk@tut.by: fixed dialyzer-spotted bug with lists:concat]
Signed-off-by: Aliaksey Kandratsenka <alk@tut.by>
Reviewed-on: http://review.couchbase.org/27755
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>