Top Plate: Add Location where PCB Fab shops can write their Job ID

[jpconstantineau]

Check with EasyEDA and other fabs to see what label to put for them to replace for the job ID.

Job ID should be between switches so that it does not show up when KB is fully assembled.

[jpconstantineau]

For JLCPCB, Add "JLCJLCJLCJLC" to a location where it's hidden. Not sure about which layer. See here for details.

For other fab shops, not sure.

[jpconstantineau]

Provided locations for Internal PCB case plates. (Top/Bottom)

[jpconstantineau]

Completed