* add matrix_diagram.md
* info.json: apply friendly formatting
* info.json: correct layout data
* info.json: alias LAYOUT to LAYOUT_all
The PCB supports multiple layouts, but I have not been able to discover how the additional layouts are wired.
* update matrix_diagram.md (thanks yulei)
* add LAYOUT_2u_numpad_plus_enter_zero with reference keymap
