info [router] longest paths lists weigth values as float

Created by: runborg

not as integers.

example:

longest paths  : stolav-gw3 <-> karasjok-gw1 (91.0), stolav-gw3 <-> evenstad-gw3
                 (85.0), stolav-gw3 <-> evenstad-gw2 (84.0),
                 stolav-gw3 <-> forde-gw2 (80.0), stolav-gw3
                 <-> kake-gw1 (80.0), stolav-gw3 <-> sogndal-
                 gw1 (79.0), stolav-gw3 <-> sogndal-gw2 (78.0),
                 stolav-gw3 <-> longyear-gw4 (73.0)