Issue #16: Modified the ScoreCalculator classes

As per discussion with Dzmitry, the ScoreCalculator functor classes will simply
accept a reference to a ProfInfo object, and use the information in that object
to calculate the score. That score is then written back into the ProfInfo
object, and (for convenience) also returned by the functor.
Merge branch 'master' of https://github.com/kgiesing/ClassScheduling

Last push, of ScoreCalculator functors (.h and .cpp files), was not successful.
Merge branch 'master' of https://github.com/kgiesing/ClassScheduling

More repo nonsense.