First "User interface" version

[pgilfernandez]

Let's start adding some information into the Docs 😄

[rodlie]

Awesome 👍

Preview (should probably make a github action for this):

We should also include images for each "section", you can easily forget what UI element the text is referring to.

Example:

## 5. Timeline

[IMAGE OF THE TIMELINE]

The Timeline is where animations and keyframes are managed....

Just a note, screenshots of the interface in this document should use the default layout (This is minor and can easily be fixed later).

[rodlie]

btw, I will add random commits when I have the time.