Puppetizing mailing lists

Allow for mailing lists to be created with a request for review.

Change-Id: I8b3b0965119418cfc9286cd20221fe38ffd06b24
Reviewed-on: https://review.openstack.org/29833
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Elizabeth Krumbach Joseph <lyz@princessleia.com>
Approved: James E. Blair <corvus@inaugust.com>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins