Reorganize demos to work closer to the manual?

[NathanLovato]

Now the manual is better organized I feel like we could improve the demos' structure a little bit too, for clarity. Some ideas just to get the conversation stated:

1. there's still a misc folder that has a bit of everything. Can we split it to fit the tutorials category of the docs?
2. how about moving physics demos to a top-level physics folder? Both 2d and 3d. Have physics/2d and physics/3d if the demo count goes up a lot, or rename all 2d physics demos 2d_* so they're grouped together?
3. Is mono clear to everyone? Is C# not an option? Mono being a compiler I'm not sure everyone would get it.
4. having C# and visual script at the root makes it so they're spread apart and surrounded by GDscript examples. What do you think of scripting_languages/c# ?

Current tutorials/ category list in the manual for ref:

[aaronfranke]

1. I recently moved the loading demos to their own folder. Any other categories we could make? Keep in mind that we have 0 demos for some of those documentation categories, and some categories don't really make sense to have demos for (like asset library).

2. I don't think this would be an improvement. Some demos use physics but aren't physics demos.

3. It's called the Mono module, and the download page mentions Mono version, so I think it's clear enough. Godot could in the future support F# etc.

4. I don't think it's necessary. We also don't need every project to have a C# version, so there will always be far fewer C# demos as long as GDScript exists. So I think it's good as-is.

[NathanLovato]

It seems I had missed your reply, sorry about that!