Added PY32 support. Tested and working with PY32F002A 24MHZ speed (8MHZ not working)

[regimantas]

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[regimantas]

In meniu set 24 MHz and it works. PY32 is 96% stm32, with litle changes. Nice to have 8 cent Arduino and NeoPixel compatible MCU :)

[ladyada]

not tested, never even heard of this chip, but it doesnt break the build so merging.