Provide power in via Pi-2 header

[MarkHaysHarris777]

@marcus: Do you know if the Pine64+ 1GB board has the DC/BAT jumpers on it? The schematic does NOT show it, and pictures of the RevB pine64+ 1GB do not show the jumper present. Unless there was a RevC which added it, the pine64 store page needs to be updated as it shows a board with the jumpers.

Pete;  there is some confusion about the 1Gb board too... apparently there is (although I can not prove this) a 1Gb board with the jumper.  I have assumed that the photo of the 1Gb board was correct (as well the 1Gb schematic) , and that the jumper came in with the 2Gb board.

IMHO the jumper is a really dumb engineering mistake;  and even the schematic for the 2Gb board has a note (which is an error) "When using DC 5v and battery supply together diconnect J9 1,2,3,4" .  The engineering problem with the jumper is that its a manual afterthoght. Of course the problem with removing the jumper is that some of the 5v pins lose power.  I leave the J9 jumper on vbatt, leave the battery plugged in, and leave the pine DCIN plugged in...  if and when the power goes out (happens in my neck of the woods) the battery (lipo) keeps things running for up to 10 hours.  The J9 jumper in vbatt position ensures that the 5v on the pins and the usb will continue. I have all of my boards (including the sopine board) jumpered this way.

I think the J9 jumper should be rethought in future boards, and should be automatic. ( there should not be a jumper!)