Working on `opt.rst`.
Replace the hardcoded `opt` psuedo code listing with a `literalinclude` from `/cmd/opt.rst`.
Reorder and update `opt_*` list to match current `opt`.
Expand sub-section titles with the function of the pass (keeping the `:cmd:ref:` part at the end to prevent the Esbonio error in vscode when a heading starts with a directive).
Move comments about `clean` and `;;` being aliases into final `opt` subsection.
Also renames `Test suites` -> `Testing Yosys`.
Blocking tasks are now capital TODO (compared to non-blocking todo).
Updated some of the todos.
Added note about which intel synth does which families.
Rename extended Yosys universe to Yosys family.
Added brief text to landing page, and also a note about the restructure and where to find old docs.
Moved todolist above ToC in preparation for disabling it in the config (so that it doesn't need it's own header).
Fixed pdf build, was previously breaking on trying to include the svg badges.
Includes CAD suite info and details on the OSS CAD suite nightly build targets.
Instructions for building from source, largely based on the readme but with some minor modifications.
Tests are still WIP, but we replaced the old test suites with a brief comment on the github workflow tests. Still needs more on the tests themselves and how to run them locally.
Also an extra todo on the index page.
Krystine Sherwin