More work on mk20dx128vlf5 port.

- Basic compilation and loading is working
- LED can be turned on/off
- USB not yet working

Output/pjrcUSB/arm/usb_dev.c

@@ -845,7 +845,7 @@ void usb_isr(void)
 		table[index(0, RX, ODD)].addr = ep0_rx1_buf;
 		table[index(0, TX, EVEN)].desc = 0;
 		table[index(0, TX, ODD)].desc = 0;
-		
+
 		// activate endpoint 0
 		USB0_ENDPT0 = USB_ENDPT_EPRXEN | USB_ENDPT_EPTXEN | USB_ENDPT_EPHSHK;