Updated mediawiki/extensions
Project: mediawiki/extensions/BookManagerv2  e6449913f530101e567e283c7573e4324ace1dfa

Migrate to JSON i18n

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

Change-Id: I7daf68e576aaae32e457d0cdd8f4c17a590c9f4c