STM32, Maple and Maple mini port to IDE 1.5.x

@IH_Cam

I think you'd need to write this as a new variant, as PIN array is defined in board.cpp and board.h

Although this could be done via #defines, this seems a bit messy.

You'd also need to update boards.txt, but I don't think platforms.txt would need to be updated

Do you have one of these devices to test with ?