Changed method convertInteractionsToFactors() to loadFactors()
Added outline for loadFactors() method: create 
factor for each vertex in graph.
Edited method loadFactors(): set factor names to vertex names for now.
Updated method loadChildToParent() to use 
interactions (edges) from a simple directed graph.
Updated method loadReactionToInteraction() to create
hashmap using interactions(edges) from a simple directed graph. 
Also updated method stringToVaraible to take a simple directed graph.
Updated method loadFactors() to include set the 
variables for each factor based on current vertex and parent vertices.