JOSS review: Improve visibility of installation instructions and developer guides

The DeepTrees docs contains installation guides only at the bottom of the main landing page here: https://deeptrees.readthedocs.io/en/latest/

However, when a user navigates away to a different section of the docs, there doesn't appear to be an easy way back to that landing page, e.g:

It would be fantastic to:

1. Make the landing page appear clearly in the table of contents above "Architectural overview", so users can return to this page easier. For example: "Introduction" or "Overview"
2. Extract installation docs into a separate, more detailed "Installation" page in the docs, under "Introduction/Overview". This would greatly improve visibility of the installation instructions (and potentially allow you to include more detailed installation instructions and tips/tricks)
3. Consider expanding "Developer guides" content so it's visible on the top level of the contents (perhaps still in a grouping, but not minimised by default). This would make it easier to quickly find the most relevant usage docs.
4. Move "Configuration" lower in the instructions, so it occurs after "Developer guides" content (it's great reference material, but is a little technical for beginner users who are just getting started)