Removed unused graph creation check.  (Exceptions will occur if graph
not created)
Algorithm change: reorder() only considers flips resulting in a W()
score higher than our current ordering.
Parameterized FlipsToCheck
Removed obsolete termination condition code.  Now using different
methods/metrics to track model progress.
Consolidated probKnowledgeXmit and probKnowledgeRecv.  Change should
have no impact on output but makes code cleaner and more readable.
Fix population size at 300 for experiments.
Reduced average size of total total knowledge and increased minimum
initial knowledge.  Will increase model execution performance, not
expected to substantively change results during exploritory phase.
Extract minimum and maximum inter-person similarity probabilities to
model-level parameters.
Fix to last commit
Extracted hard-coded S() parameter, sigmoidCenter to a model parameter.
Effective for new W() and S() functions; diffuse() and reorder() still
need to be adapted to use W().
Refactored reorder() to use W()
Refactored diffuse() to use W()