Rework board per Kieran's suggestions

- Route the USB differential pairs together, and without vias
	- Had to move back to the SSOP package because the QFN package
	  would require a crossover (yes, no, it doesn't make any sense)
- Ground fill
- Hand-route
- Redistribute passives to be more reasonably laid out
- Power the FTDI chip off VBUS_HOST instead of VBUS_DEV
- Add TX/RX LEDs
- Add a ferrite bead