Localisation updates from https://translatewiki.net.

Change-Id: I68bc57f279c9829c12ff2458ae4929593639a856
Customized description

Change-Id: Ic08beab8b56f1e093599d39898dcc8f3cf22a339
Migrate to JSON i18n

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

Change-Id: Id0a54ea2f0e021068a86430764dd86fc72fd982c
Complete migration to JSON i18n

In the first pass, one group hadn't been migrated.

Change-Id: If5ca30c5fd95c9f54140d73e66c4758511d289c2