Updates to code descriptions output by HELP with minor refactor

[noobydp]

I noticed that you modified the HELP code so that it includes the 'standard' g/mcodes. I have added reasonable descriptions for each of the codes (as much as possible).

I have done basic testing on a small desktop 3 axis CNC machine, but have not run large/complex jobs. The changes should be relatively safe IMO.

For reference - I'm creating a custom Fusion 360 Post Processor and might end up with custom posts for vanilla klipper vs klipper-for-cnc. I wanted a comparison of the g/mcodes available in each, and stumbled across the HELP function... which led to this. I assume there's no wide-spread need for this to be accurate, but figured it couldnt hurt.

[naikymen]

This is great thank you! I'll review and leave comments.

[afbenevides]

@noobydp that seems interesting, do you plan on sharing those post- processor? I will be starting a small CNC build based on the klipper-for-cnc, and I would have interest in working on available post-processor for Fusion 360 if available.

[noobydp]

@afbenevides i sure can, but I'll probably be a few more weeks until I can finish.

Right now I'm using this MPCNC PP, it works fine but I wanted to make one that's more specific for Klipper, and add some features.

https://github.com/flyfisher604/mpcnc_post_processor

[afbenevides]

Thanks for the link.

[naikymen]

Done :) thanks a lot!

I made small changes before merging: b455ef3e062e3edba2024adddc8455027be0b987

The most important being moving M114 and GET_POSITION out of the handlers list. Those required when_not_ready=True.

Please check though!