get collator via http instead of s3

This is a workaround for the missing s3cmd, which itself
will be unnecessary once CBLT-235 is closed.

Change-Id: If12d1d4a3a7b794943a1d1ccd6cb9231b6fbce4a
Reviewed-on: http://review.couchbase.org/33681
Reviewed-by: Chris Anderson <jchris@couchbase.com>
Reviewed-by: Traun Leyden <tleyden@couchbase.com>
Tested-by: Traun Leyden <tleyden@couchbase.com>