CartographerAdapter: removing hard coded set of laser scanner names

on ARMAR-6 and ARMAR-DE, we must specify the laser scanners now. See "laser_scanners" field, which should be "LaserScannerFront,LaserScannerBack".

Test on ARMAR-6:

• the conversion from polar to Cartesian has changed. Must fix Hokuyo scanners (add +90 deg).