Localisation updates from https://translatewiki.net.

Change-Id: Iaf949be14bf1b0710a0ed94a7139347f70ddfb74
Migrate to JSON i18n

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

Change-Id: Iee5ca4d40b97160f384250b94892defa56843a07