Add support for HiGHS

[codecov[bot]]

Codecov Report

Merging #194 (5bf8beb) into master (8ad4771) will decrease coverage by 0.02%. The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master     #194      +/-   ##
==========================================
- Coverage   85.30%   85.28%   -0.03%     
==========================================
  Files          16       16              
  Lines        3158     3160       +2     
==========================================
+ Hits         2694     2695       +1     
- Misses        464      465       +1     

Impacted Files	Coverage Δ
src/utility.jl	81.78% <50.00%> (-0.22%)	:arrow_down:

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[hellemo]

A better solution would be nice, but at least this works for now.

I did try this with HiGHS for a few small test problems, and they all solved without issues .

[ccoffrin]

As long as someone tested it, this is fine by me.