Replace WiringPi code examples with equivilent, and much more useful RPi.GPIO examples.
Add pin setup to overlays- IN/OUT, plus polarity Active HIGH/LOW
Add PNG renderer to turn JSON overlays into usable pinout images
Change pincount to useful figure that details compatibility - HAT, 26 pin, etc
Remove "exclusive" from JSON since all defined, non-i2c or SPI pins will be exclusive anyway