[Fedora-spins] Fedora 28 Spins page: spin/labs owners please test

Greetings. Per this fesco ticket: https://pagure.io/fesco/issue/1714 I have created the Fedora 28 spins/labs page: https://fedoraproject.org/wiki/Releases/28/Spins All spin maintainers/owners/interested parties should test their spins and at least update this wiki page with beta/final testing. Spins that don't have at least one tester at Beta may be dropped and not shipped in Final, so PLEASE make sure at least someone tests. Spin maintainers are also encouraged to test their spin more often and make sure it's composing correctly every day for Branched f28 and rawhide. Thanks, kevin