feedback from Werner

1) R16 might need a /250V indicator to match C31
2) FBx have no values, one idea is to put the manufacturer
   part number into the value field, see U1 and D1 in cntr
3) the mini-usb connector symbol is quite ugly. to make it even
   more weird, it has two unused pins that don't correspond to
   anything in the footprint either. how about stealing the one
   from gta02-core or ben-wpan (the latter got it from the former) ?
   ben-wpan/components/mini_usb_b.lib
4) (that's something inherited from kicad) you have a nice example
   for the trouble with the default symbols when you look at the
   font sizes in FB2, then C27, and finally +3.3V (all are near
   each other)