Add support for Coral Dev Board Micro

[RerikOp]

Feature request to add the board to platformio: https://coral.ai/docs/dev-board-micro/get-started/#

[nicklasb]

That sure is a cool product. Anyone have actually tried it out?
I haven't really found a competitor to it.

[mattsoftware]

I have just bought one and I am looking at a way to develop for it using platformio. I am not familiar with the way platformio handles boards etc. There is a link to the arduino board manager on that page (https://dl.google.com/coral/micro/package_coral_index.json) if that helps.

[RerikOp]

My team and I abandoned this board as we had many problems with it not executing the firmware (after a few flashes, even simple LED toggles did not work anymore). We tried almost all combinations from OS, python/arduino flashtool and reset methodologies. All with the same result. So either we just received some kind of broken board, were just incompetent, or you can prepare for a lot of pain getting this board to run what you actually want ;)