New one sided PCB for toner transfer production at home.

Second version of PCB includes level shifting FETs on the I2C lines. These are
needed because PIC is operating from 3 V regulator while Raspi is using 3.3 V.

A second LED was added on PIC GP5. This can used to show active sleep mode
of the power supply.

Holes to three ground jumper wires have been added.

Update circuit diagram.