* add wpa-supplicant package dependency
* removed no longer working 'db-bahn.login' and 'wifionice.login' auto-login scripts
* added the new 'wifibahn.login' script for auto-logins to captive portals WIFI@BAHN (DE),
  run tested on a single ICE (station logins are currently unsupported!)
* vodafone.login prepared to support free/time limited logins (still WIP!)
* change return code handling in login scripts and travelmate
* refine f_wifi function
* fix a few conercase issues

Signed-off-by: Dirk Brenken <dev@brenken.org>