CCBC-457: Don't use couchbase:// uri for --host parameter

The --host parameter should be converted to http:// to support older
semantics.

Change-Id: I1531c3723c9180479de76baa40257d3c11321979
Reviewed-on: http://review.couchbase.org/38743
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Brett Lawson <brett19@gmail.com>