Release Revision 2 (update)

This revision is electrically equivalent to rev2, but
includes a fancy MiSTeX logo on the PCB
and replaces the ferrite bead with another part that is in stock.

Release Revision 2

This release fixes some minor issues that the
largely functional rev1 had.
What happened:

The side switches are now latching, as they always should have been (my mistake)
The USB Boot line of the RP2040 is now connected to the HPS, allowing to reflash it via HPS.
Updated the project to KiCAD8
Added a HOWTO for ordering from JLCPCB
Used our cute mascot also on PCB
Added a solder jumper to optionally connect RP2040 USB VBUS to +5V (will find out if we need it)
Moved the ground vias in the U.FL scope probe connectors out of center to prevent shorts when using untented vias

This board has not been manufactured yet, but as the previous revision has been working
in all important regards, I am quite confident on this one.