Add reverse lookup provider "Das Telefonbuch" (DE).

Change-Id: I0ad72bb3e57da3d27fb1c50c58c112234c39b585
Refine regexes for Das Telefonbuch.

Looks like private and business numbers have a slightly differing
format.

Change-Id: I7eae982fe81cf890686f49b88417e604ba0171a0
Dialer: remove obsolete values-en-rXX

We have a dedicated selector for search language,
so there's no more need to keep this.

Change-Id: I47bf4fb6dbe7881fb54949de4542ffe42331a009