Create talk namespaces matching main namespaces
Summary:
Wolfplex wiki has two custom extra namespaces, Bulletin: and Event:
The associated talk namespaces aren't automatically created, so this change
creates them explicitly.
Test Plan: Check https://www.wolfplex.org/wiki/Spécial:Toutes_les_pages before/after
Reviewers: dereckson
Reviewed By: dereckson
Differential Revision: https://devcentral.nasqueron.org/D1501