Merge pull request #1416 from thinkyhead/cleanup_pins

Marlin/Marlin.h

Marlin/boards.h

Marlin/pins.h

Marlin/pins_3DRAG.h

Marlin/pins_5DPRINT.h

Marlin/pins_99.h

Marlin/pins_AZTEEG_X1.h

Marlin/pins_AZTEEG_X3.h

Marlin/pins_AZTEEG_X3_PRO.h

Marlin/pins_BRAINWAVE.h

Marlin/pins_CHEAPTRONIC.h

Marlin/pins_DUEMILANOVE_328P.h

Marlin/pins_ELEFU_3.h

Marlin/pins_GEN3_MONOLITHIC.h

Marlin/pins_GEN3_PLUS.h

Marlin/pins_GEN6.h

Marlin/pins_GEN6_DELUXE.h

Marlin/pins_GEN7_12.h

Marlin/pins_GEN7_13.h

Marlin/pins_GEN7_14.h