I have made one change to `gcode.py` to support quoted parameter values. I have added support for the basic `M118` command (see https://reprap.org/wiki/G-code#M118:_Echo_message_on_host). I have also added a `RESPOND` command that takes extended parameters. `ECHO` might be a better name than `RESPOND` but is already defined in `gcode.py`. Signed-off-by: Alec B. Plumb <alec@etherwalker.com>
Welcome to the Klipper documentation. The overview document is a good starting point.