Add aditional documentation on pico install. Primarly Image with labeing.

[smb123w64gb]

Id like to add a image with test points labeled to help others who may attempt to install in the future. Ill try finding them and labeling them when in have time. A good image is the one on wiiubrew.

[Viperbite]

GND is taken from TP167, a randomly selected test point. I didn't want to clean the protective mask of the board. RP2040 is glued on double-sided tape on the entire back, to avoid a short circuit on the board.