Replace ColPack with SparseMatrixColorings

[gdalle]

Fix #237 by replacing the dependency on ColPack.jl with a dependency on SparseMatrixColorings.jl. Similar to #230, I use the ADTypes.jl coloring framework so that other coloring algorithms can be easily inserted.

In what follows, I'm careful to differentiate between

• ColPack (C++): the original library
• ColPack.jl: the Julia bindings developed by @michel2323, @amontoison and (unwillingly) myself

Upsides

Very relevant:

• ColPack (C++) is 30k LOCs of unmaintained, unreadable C++ that hasn't been touched in half a decade.
• SparseMatrixColorings.jl is 1.5k LOCs of maintainable, readable pure Julia with good docs and reliable tests.
• SparseMatrixColorings.jl seems faster than the upcoming release v0.5 of ColPack.jl, at least for the natural ordering of vertices

A bit less relevant cause it can be fixed with lots of sweat:

• The current release v0.4 of ColPack.jl uses ColPack (C++) in a very inefficient way, with no option for bipartite coloring
• We're working with @amontoison to code more efficient bindings in ColPack.jl v0.5. This is hard to achieve and still rather buggy, mainly because ColPack (C++) lacks some documentation:
  • https://github.com/exanauts/ColPack.jl/pull/20
  • https://github.com/exanauts/ColPack.jl/issues/21

Downsides

• SparseMatrixColorings.jl cannot yet do everything that ColPack (C++) does. See the following issues for tracking:
  • https://github.com/gdalle/SparseMatrixColorings.jl/issues/15
  • https://github.com/gdalle/SparseMatrixColorings.jl/issues/14

[github-actions[bot]]

Package name	latest	stable
CaNNOLeS.jl
DCISolver.jl
DerivativeFreeSolvers.jl
JSOSolvers.jl
NLPModelsIpopt.jl
OptimalControl.jl
OptimizationProblems.jl
Percival.jl
QuadraticModels.jl
SolverBenchmark.jl
SolverTools.jl

[tmigot]

@amontoison @gdalle Please squash and not rebase, thanks!