Add Telenor Unified

New APN per https://jira.cyanogenmod.org/browse/CYAN-3338

Referenced: http://anderse.wordpress.com/2012/07/28/telenor-mobil-norway-apn-settings/

Change-Id: I119e0691128802cbfb3821ad9b17e6f49e20765e
Cleanup and consolidate APNs for providers using Telenor NO network

 * Remove "Telenor MMS" - Was merged into "Telenor" in a previous patch
 * Rename Ludo to Ventelo - Ludo doesn't exist anymore
 * Merge "Mobitalk Internet" and "Mobitalk MMS" into a single APN

Change-Id: I77ff06d6c8d6021cd1887468bbeb7ac9315e68bb
Add a default MMS UA

The default user-agent isn't set, which makes
TelephonyManager.getMmsUserAgent() return an empty string when a
device doesn't have one in its own overlays. Every hardware should
set its own unique name for this, but add a default value for cases
in which is is forgotten.

Fixes android.telephony.cts.TelephonyManagerTest#testTelephonyManager

Change-Id: I8a648014873319ea0d0f1089495d6777b8a1b8bf