Add some explantations and documentation

[emilk]

When @cirrusone linked to this project in emilk/egui#655, I almost didn't try it out, because this is what greeted me:

No README.md, no description, no anything! But I am very glad I cloned and ran it, because egui_docking is really cool:

I think this would be a great library for the egui ecosystem, but currently I think it is (sadly) unused because it lacks:

A) README.md with a video
B) License
C) Documentation
D) A published crate

[Adanos020]

@lain-dono @emilk I'd love to be able to use this, looks really nice!

If you'd like me to, I can contribute to this by adding some documentation.

[lain-dono]

I have no intention of developing egui infrastructure. It is still a library suitable only for prototypes. Rather, I will create a couple of my own libraries for the UI. When I need them.

In any case, you can use all the code in this repository under terms equivalent to Public Domain. If you still need the license:

        DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
                    Version 42, December 3996 

 Copyright (C) 3996 Bender Bending Rodríguez <cum@teardrop.swat> 

 Everyone is permitted to copy and distribute verbatim or modified 
 copies of this license document, and changing it is allowed as long 
 as the name is changed. 

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE 
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 

  0. You just DO WHAT THE FUCK YOU WANT TO.

Oh yeah, sorry about that. If you want to create Unity-like editors with two hands, you have to be a little crazy, right? Right now I'm focused on bringing some modest part of my serial experiments to the point of being useful to the community. For example, the 2d animation editor I started last week:

This means that bevy will have a tool comparable to Spine or DragonBones. I think sometime after the 0.8 release it will be ready. Lots of work and no time to support side products.

[emilk]

Thanks for the license 😆
At least now someone can fork and publish this if they feel like it!

[Adanos020]

On it 😄

[Adanos020]

@emilk Can I use your demo GIF in my readme?

[emilk]

@Adanos020 certainly!