Some more documentation progress

[Jutho]

This includes a major restructuring (breaking down long pages into separate pages) and a complete rewrite of the Sector documentation. This could become the manual page for TensorKitSectors.jl in time, but for now I would still include it here.

By lack of a good Markdown formatter, I switched to breaking lines at natural places (end of sentence, subsentences, …), like one might do with LaTeX documents. Maybe that strategy can lead to clean git diffs in future (potentially smaller) doc changes, but I am open to other suggestions.

This would very much benefit from some proofreading by e.g. @borisdevos , @leburgel , @lkdvos .

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/tensors/linalg.jl	0.00%	2 Missing ⚠️

Files with missing lines	Coverage Δ
src/tensors/braidingtensor.jl	68.29% <ø> (ø)
src/tensors/indexmanipulations.jl	73.42% <100.00%> (+0.09%)	⬆️
src/tensors/linalg.jl	82.59% <0.00%> (ø)

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[github-actions]

After the build completes, the updated documentation will be available here

[lkdvos]

I think I managed to resolve most of Boris' comments now, I wonder if it makes sense to simply go ahead and merge this in its current state. At least some of the sections that still refer to old factorization functions are now cleaned up, so we should put a little haste on this.

[lkdvos]

@Jutho I think it would be nice to simply merge this, let me know what you think.

[Jutho]

On the one hand, I think I don't have local changes so I am not opposed to merging this. However, my Markdown formatter screwed up some of the markdown like the note blocks, and there might be other issues still as well:

So I think a bit more review and corrections are still necessary. I'll try to make some time tonight.

[borisdevos]

I had the same with note blocks, but that's because I replaced every "." with a "(shift+enter).", so that ruins note blocks which need to be tabbed. I also saw this issue for lists.

[lkdvos]

You should probably quickly check everything is now done correctly, but I did read through the entire docs again, changed the markdown into one sentence per line, and fixed a few typos etc.
For me this is now definitely good to go.