Updated mediawiki/extensions
Project: mediawiki/extensions/ConventionExtension  e5974dd6f0abac3e4a4b8ccfd1f270df4014b0a1

Migrate to JSON i18n

Procedure per https://www.mediawiki.org/wiki/Manual:GenerateJsonI18n.php
with shim.

Change-Id: I703c33c1532d3caa17b44a24d7e5322590754a35