Emacs Style Help Keybindings Mode

[VisenDev]

It would be nice if there was a mode/extension that rebound C-h to support emacs help commands, like C-h b for describe-bindings, C-h k for describe-key, or C-h f for describe-function. Currently the discoverability of lem is a bit limited coming from emacs. I'm ending up needing to grep the lem source code to find the source code for various things.

I might work on this myself if I get some time, but I wanted to create an issue to bring awareness and discussion.

[VisenDev]

related: #407

I am not suggesting that C-h do this by default, but rather that there should be a mode to do this if desired. Also, many of the calls like describe-function or describe-variable aren't implemented in lem, so this issue at the very least concerns adding those, even if the keybindings are not added