* Move existing documentation to its own `doc` folder
* Convert setup_base_image_debian to Markdown
* Convert setup_base_image_other to Markdown
* Convert setup_base_image_raspi3 to Markdown
* Convert setup_babse_image_raspi4 to Markdown
* Convert setup_base_image_rock64 to Markdown
* Convert setup_base_image_rockpro64 to Markdown
* Update filepaths in code to point to new `doc` directory
