Get rid of localAddr derived from REST request

Localhost address gets derived from REST request we should probably remove this practice as it is output of the REST endpoints depends on the socket which they are called on.

The localhost should always be of the address family configured. 

See, menelaus_util:local_addr, http://src.couchbase.org/source/xref/cheshire-cat/ns_server/src/menelaus_util.erl#416

Example usage here, http://src.couchbase.org/source/xref/cheshire-cat/ns_server/src/bucket_info_cache.erl#219