add monitoring for search.wm (Apple dict bridge)

see RT #6128 for the request for this to be added

adds the check to a mediawiki role, not to
search module, because search.wikmedia.org is the
Apple dict bridge and the Apache site for it is configured
in mw module and unrelated to elastic

then uses the role class on terbium, so that we
just get a single monitoring check, we don't want
one per appserver. so gotta put it somewhere and terbium
is mwdeploy obviously

not creating the virtual monitoring host anymore
as in PS1, just using terbium

we are checking this URL:

https://search.wikimedia.org/?lang=en&site=wikipedia&search=Wikimedia_Foundation&limit=1

for the string "Wikimedia_Foundation"

Change-Id: I69537a84ba225b51900ae1078cce88ec25d3b514
RT: 6128