[documentation] Add tutorials & citation

[amontoison]

close #95
cc @adrhill

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Add the tutorials prepared for AD2024 in the documentation, updated for PPoPP25 next month, and using the latest visualization features of SMC.jl.

Adrian and Guillaume, is it already possible to display the sparsity pattern on which we apply a coloring with all nnz in black?
A workaround will be to set all colors to black but it could be nice to have an option sparsity_pattern in show_colors (if it doesn't exist already).

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (172fd12) to head (1cb0751).
Report is 1 commits behind head on main.

Additional details and impacted files

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[gdalle]

Thanks for this initiative!

I see two ways to make this even better:

• Say a couple words about each variant of coloring instead of just dropping the result on the user. What problem is each one supposed to solve? How does it compare to the previous ones? In particular, the point of bicoloring is not so obvious in this case (since the matrix is symmetric, it will always be worse than symmetric coloring?)
• Can we avoid carrying and versioning an mtx file in the repo? We could download one on the fly instead with MatrixDepot.jl.