Add polygon

[tmigot]

#161

[codecov]

Codecov Report

Merging #167 (7a083e1) into main (3341bbf) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #167   +/-   ##
=======================================
  Coverage   99.55%   99.55%           
=======================================
  Files         715      718    +3     
  Lines        6240     6281   +41     
=======================================
+ Hits         6212     6253   +41     
  Misses         28       28           

Impacted Files	Coverage Δ
src/ADNLPProblems/polygon.jl	100.00% <100.00%> (ø)
src/Meta/polygon.jl	100.00% <100.00%> (ø)
src/PureJuMP/polygon.jl	100.00% <100.00%> (ø)

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[tmigot]

I think we miss the initial guess for this one. Couldn't really read it here https://bitbucket.org/optrove/sif/src/master/POLYGON.SIF or not clear in the COPS report.

[dpo]

Here's one: https://vanderbei.princeton.edu/ampl/nlmodels/polygon/polygon2.mod

[tmigot]

Here's one: https://vanderbei.princeton.edu/ampl/nlmodels/polygon/polygon2.mod

Great, thanks! I adapted it to the current model.