Additions to readme and debugging output during keymap creation

[davidshepherd7]

I made some other changes that might be useful while I was trying to figure things out for the issue I raised:

• Clarify how to generate shifted keys
• Add example for generating a ctrl with the space key
• Make numbered lists in the readme into markdown recognised lists
• Add some debugging output during keymap creation

[alols]

Awesome work! Thank you! :)

[davidshepherd7]

Glad to help out, thanks for the great tool :)