Unified default lang redirect from m. & zero. Adding three carriers for testing, too.

* Default language for the carrier is now set in one location
* XL Indonesia is changed to "id" default language
* Old code did NOT redirect unknown carrier zero.wiki to en.zero.wiki. Now redirecting.
* Refactored to support default relative redirect path for direct zero. and m. access from partners.
* All partner direct access to zero. and m. going to default (language options selection page).
* Adding three additional carriers for testing.

Change-Id: Ifda2dcabaa08f5df7b22b3b1d726f21882bbca36
Merge "Unified default lang redirect from m. & zero. Adding three carriers for testing, too." into production