Add Ubuntu-10.04 buildslave Dockerfile

Change-Id: I847ead3e6f33939dcb7647de9bf47afc0bd581eb
Reviewed-on: http://review.couchbase.org/39826
Reviewed-by: Chris Hillery <ceej@couchbase.com>
Tested-by: Chris Hillery <ceej@couchbase.com>