CBLT-262:  copy edition specific license file before making zipfile

see sync_gateway commit:  72876bd6e49815f61ede04874c290fde47c0d5b0

Change-Id: I092c1b29007a39984c348b3392128eb258e664a0
Reviewed-on: http://review.couchbase.org/35482
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>