Significant improvement to mincost_flow

[ndinsmore]

Fixed mincost_flow to have much better performance.. around 10000x faster for cases with 500 nodes. Changed mincost_flow arguments to be more consistent with traditional problems ie. primary demand is for nodal values. edge_demands can be set with keyword argument

Depreciates baseline edge_demand arguments.

Below is the benchmarking I did.

[codecov[bot]]

Codecov Report

Merging #23 into master will decrease coverage by 1.33%. The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #23      +/-   ##
==========================================
- Coverage   66.98%   65.65%   -1.34%     
==========================================
  Files          10       10              
  Lines         418      428      +10     
==========================================
+ Hits          280      281       +1     
- Misses        138      147       +9

Impacted Files	Coverage Δ
src/mincost.jl	50% <50%> (-15.39%)	:arrow_down:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update eff807b...d3b2543. Read the comment docs.

[codecov[bot]]

Codecov Report

Merging #23 into master will decrease coverage by 1.33%. The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #23      +/-   ##
==========================================
- Coverage   66.98%   65.65%   -1.34%     
==========================================
  Files          10       10              
  Lines         418      428      +10     
==========================================
+ Hits          280      281       +1     
- Misses        138      147       +9

Impacted Files	Coverage Δ
src/mincost.jl	50% <50%> (-15.39%)	:arrow_down:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update eff807b...78c9cb3. Read the comment docs.

[coveralls]

Coverage decreased (-34.3%) to 65.654% when pulling d3b2543fcf2a47d4b308761313ab7aca3ae6680b on ndinsmore:mincost_flow_fix into eff807b2197fbf665bbb7178624ef4d4f64fb7d7 on JuliaGraphs:master.

[ndinsmore]

Review of the coverage shows that the lines were clearly hit and missed by the sampling. I can add more tests that would torture the function if needed.

[matbesancon]

hi @ndinsmore, thanks for the work and the benchmarks added. Codecov is a bit tricky, if you want to add more tests that would cover more cases of the functions that would be helpful. If this gets too cumbersome we will just not consider the cov information

[ndinsmore]

@matbesancon I think that I have made all the changes that you requested.

[matbesancon]

great, thanks again, I'll review everything tomorrow

[matbesancon]

thanks @ndinsmore!