CBD-1249:  add ubuntu-1204-x64.ini

Change-Id: I5eccea96de406c03e0af7bf4344e9bdc5586dd67
Reviewed-on: http://review.couchbase.org/39676
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>