Design for daughterboards

Problem environment

Several competing architectures lead to different product designs, all of which benefit from optional features. Satisfy most or all such contenders by designing for a stackable daughterboard assembly, to be arranged by the user themselves.

Daughterboard candidates

1. Supercapacitor array (mobile power)
2. Energy harvesting (ecologicalal operation)
3. Sensor environmental sampling
4. Actuator environmental activity
5. RFID configuration with a smartphone

Resolved in 1c8ea48, with pogo pin pad array breaking out GND, 3V3, SCL, and SDA.