add remaining BastardKB boards

[burkfers]

This change adds pretty staggered layouts for the remaining BastardKB boards: The entire Charybdis and Dactyl families, including

• Charybdis Nano (3x5)
• Charybdis Mini (3x6)
• Charybdis (4x6)
• Skeletyl
• TBKMini
• Scylla

The jsons have been hand-formatted to be as human-readable as possible.

Examples (both yaml and resulting image) can be viewed here: https://github.com/finrod09/bastardkb.github.io/tree/keymap-images/assets/pics/layouts

pending checks that I've used the correct stock LAYOUT macros

[burkfers]

I've changed the LAYOUT macros to match qmk info.json. Quentin has given his approval on the visuals. Ready to go on my end!

I'll be happy about any feedback you might have.

[caksoylar]

Thanks, I appreciate you contributing! It looks like you covered all the bases w.r.t. naming and layouts. Creator approval is certainly a higher bar than I set so far and it's good to have :)