Localisation updates from https://translatewiki.net.

Change-Id: Ieb1e89d32ac2d002a69a926aa1e048a4641e2ef3
Migrate to JSON i18n

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

Change-Id: Ib61ab9ef00939b8191dbc17d15fbe51c1f07b63c