(bug 15434) Periodical run of currently disabled special pages

Stole mutante's refreshlinks class used for bug 16112.
The idea would be to update only one page per cluster at a time, two times per year.

* 1 UTC: servers less busy; doesn't overlap with any deployment window but is not too far from time used for some. https://wikitech.wikimedia.org/view/Deployments
* Same cluster/monthday syntax as per refreshlink, +10 days to avoid overlap.
* Each query page has its defined months.
** List from $wgDisableQueryPageUpdate, restored CamelCase in case updateSpecialPages.php cares.
** We're lucky because the disabled pages are 6 globally and 12 for en.wiki (since years ago).
** The 6 pages disabled only on en.wiki are left behind for now.

Ideally, I guess we should use Tuesday and Thursday of each week in each month.
s1 in the first Tue, s2 in the first Thu, s3 in the second Tue etc.
This way it would always be in worktime and never same day as MW bi-weekly deploy.
I've no idea how to do it, though. http://docs.puppetlabs.com/references/latest/type.html#cron

Change-Id: Ia5bd4c90f8be3d047f0752536170783eb6817072