PICO pcb reworked

[j3qq4hch]

I really like this project (although still had no chance to try it myself). But I noticed that the quality of the hardware source files does not match the quality of the software. This is understandable, no one can do everything perfectly.
So I tried my best to format the hardware side of Pixelblaze PICO better. Couple important notices:

• The schematic was not changed. Everything is still connected exactly the same way it was before.
• Component placement was not changed. All the components are still in the same places as they were before

And now to the changelog:

• All the parts were replaced with better ones. For passive parts also footprints were replaced with more IPC compatible ones (0% problems when reflow soldering)
• Schematic symbols for all parts were redone for the schamatic to look good and be more readable.
• DRC settings were updated (DRC settings for JLCPCB were used which are compatible with majority of PCB manufacturers)
• Vias diameter reduced from 0.35 to 0.3 mm fix some clearance errors
• All the parts were moved to managed libraries, missing 3d models were added. This allowed me to generate a complete 3d model of the device, which is available here.
• Routing was enhanced where needed (less closed angles and shorter signal paths overall)
• All the traces were rounded where possible for aesthetic reasons.
  I hope you will find this PR appropriate. If so, there are some more things that can be done to this PCB to make it even better, let me know.

A couple screenshots of the 3d model just for the reference:

[simap]

Wow, that is pretty awesome! Thanks for the PR.

[j3qq4hch]

Do you think it can be merged into master?