MB-7250:  remove siging.  Even though this project file works correctly
when make is called from the command line in a native shell, it does
not work either in an ssh session, nor when the command is issued by
buildbot.  Need to produce it unsigned, then sign from the command line,
and then zip it up.

Change-Id: I91eeefe823c9a8046b6a4595b027903932714926
Reviewed-on: http://review.couchbase.org/30538
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>