Detect subproblem infeasibility

[guimarqu]

Close #361

[codecov]

Codecov Report

Merging #364 into master will increase coverage by 0.14%.
The diff coverage is 87.50%.

@@            Coverage Diff             @@
##           master     #364      +/-   ##
==========================================
+ Coverage   75.89%   76.04%   +0.14%     
==========================================
  Files          51       51              
  Lines        3755     3761       +6     
==========================================
+ Hits         2850     2860      +10     
+ Misses        905      901       -4     

Impacted Files	Coverage Δ
src/Algorithm/colgen.jl	83.11% <87.50%> (+1.65%)	⬆️

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