Please backport mediawiki 1:1.27.1-2 (universe) from zesty

[Kunal Mehta]

Please backport mediawiki 1:1.27.1-2 (universe) from zesty to xenial.

Reason for the backport:
========================
MediaWiki was unmaintained in Debian and removed from there and Ubuntu for quite a while,
and recently I have picked up the packaging and maintainance of it. The newer version is included
in yakkety, and it would be nice to also have it available for LTS users in xenial-backports.

Testing:
========
Mark off items in the checklist [X] as you test them, but please leave the checklist so that backporters can quickly evaluate the state of testing.

You can test-build the backport in your PPA with backportpackage:
$ backportpackage -u ppa:<lp username>/<ppa name> -s zesty -d xenial mediawiki

I already have built and tested packages for xenial in my PPA: <https://launchpad.net/~legoktm/+archive/ubuntu/mediawiki-lts>.

* xenial:
[x] Package builds without modification
[x] mediawiki installs cleanly and runs
[x] mediawiki-classes installs cleanly and runs

Reverse dependencies:
=====================
The following reverse-dependencies need to be tested against the new version of mediawiki. For reverse-build-dependencies (-Indep), please test that the package still builds against the new mediawiki. For reverse-dependencies, please test that the version of the package currently in the release still works with the new mediawiki installed. Reverse- Recommends, Suggests, and Enhances don't need to be tested, and are listed for completeness-sake.

mediawiki
---------
* libreoffice-wiki-publisher
  [ ] yakkety (Reverse-Suggests)
* git-mediawiki
  [ ] yakkety (Reverse-Suggests)
* php-wikidiff2
  [x] yakkety (Reverse-Recommends)