Add option to show key under transparent keys, and find the layer name during parsing

[FancyFurret]

Hi, I needed these two features and implemented them. I think others might want them as well

• Added an option to show the keys under transparent keys. Now you can see what key will actually be sent when that transparent key is pressed. If there are multiple ways to get to a layer, and the transparent key could send different things based on the current path, then it will show all the possibilities (I imagine this would be pretty rare, my layout does not do this). The style of these is still set to trans, so they can be styled as such.
• During QMK parsing, it will find the layer names from their indexes. This way parsing qmk c2json files will show the correct destination layer for MO/LT/etc.

Let me know if you have any questions!

[FancyFurret]

Example of what showing the key under the transparent keys looks like:

[caksoylar]

Pinging on this, see my questions above.