Some fixme in bluetooth.c

Working on NRF.setAdvertizing there are some FIXME on the road (jswrap_bluetooth.c)
Actually I reach these:

• sd_ble_gap_device_name_set
  
• sd_ble_gap_adv_data_set
  
• adv_data_encode
  For the first one, there is an idea what to do.
  The others are some more questionmarks on a long long way.
  
  

Generally, I would prefer not to have device related code seperated by #if in a core file
@gordon, whats your point to that, could we move them to bluetooth.c ?