Hardware change list for rev3

[festlv]

• 220uF electrolytic capacitor near ESP32/MHZ19
• Fatter 5V/GND traces (at least from ESP32 to MHZ19)

[skrubis]

My last commit addresses the following:

• Added bulk capacitance close to esp32
• added more girth to 3v3, 5V and GND nets, added thermal reliefs where applicable
• fixed text from previous revision being mirrored where it should not be
• added a lot of text regarding the correct side for components/soldering
• cleaned up routing in general, made it a bit more compact
• added SAO 1.69ibis connector on the abdomen for future extendability
• covered up exposed traces on the neck
• lots of other various tiny tweaks