Minor issue in SetCover

[danyaljj]

Potentially a bug:
I think this line should be changed to:

SetCoverSolverDataModel.cityContainsNeighborhoods.populateWith((c: City, n: Neighborhood)=> n.getParentCity == c)

I am not sure how similar lines in the test work either: https://github.com/IllinoisCogComp/saul/blob/310ca43a618b7928c5c1a352a4059a0c87578780/saul-examples/src/test/scala/edu/illinois/cs/cogcomp/saulexamples/SetCoverTest.scala#L26

[bhargav]

Since the condition has .populateWith(_ == _.getParentCity), I believe the first _ is assigned the City and the second the Neighborhood parameter. Hence the behavior looks correct. Though we should fix it for readability.

http://www.codecommit.com/blog/scala/quick-explanation-of-scalas-syntax

[danyaljj]

That's what I thought; although intelliJ seems unhappy: "comparing incompatible types".
it's probably a false alarm ...