add check for https://phabricator.wikimedia.org

adds a custom check to monitor phab behind misc-web
using check_http with -S gives us certificate monitoring as
well. we ask misc-web-lb for a specific URL and we also
check for string "Wikimedia and MediaWiki" in there to make
sure we are not getting just a 200 with some other content

T957

Change-Id: Ie790fd2e3b607e927260288c1c1adfaf95be0fee