replaced usages of Graph with Model
replaced @selected_model_node with get_node_model()
fixed node duplicates.
added model updater
removed old references to inEdges and outEdges
fixed broken init
added recalc; removed default assumptions on data calculations
fixed node assumption setting for context and personality nodes.
resolved TODO: complete node moved into modelBuilder, duplicates ignored
re-fixed demo graph drawing
resolved stochatic graph issues