Modifications to documentation

[JuanSapriza]

We have to review the state of the documentations. Some tasks

• Look for inconsistencies
• Organize the tutorials in folders
  - [ ] Add more peripherals
• Modify the README.md to give a short introduction and redirect to Read the docs
• Modify the X-HEEP logo so it is dark-mode compatible. eg:

[JuanSapriza]

@davideschiavone @JoseCalero Maybe you guys wanna take a look over the inconsistencies (you can see them if you cd docs & make clean html.

Note that the documentation is pointing at this branch now.

[davideschiavone]

there are missing pip dependencies in the conda environment that you may want to add as:

pip install sphinx
pip install myst-parser
pip install sphinx_rtd_theme

some images are missing (or their link is broken), e.g. x-heep/docs/build/html/How_to/ides/img/debug_screenshot.png

[JuanSapriza]

@JoseCalero Merge SVP

[JoseCalero]

Approved