* start upstreaming cmdline patches

* pcbnew --plot doesn't pick up global clearance settings, so we end up
  with the hard-coded defaults. See Preferences -> Dimensions -> Pads
  Mask Clearance. It is not quite clear whether settings are stored in
  the .pro or .brd files, there seems to be a difference depending on
  whether the .brd file is opened directly via pcbnew, or via the kicad
  binary and .pro file. Some values are in the .brd file but it's not clear
  how they can be changed from the GUI. These values need to come from the
  .brd file, cannot be passed in via the command line.