removed tests from BayesianModel, removed redundancy in active_trail_nodes
removed tests from BayesianModel, removed redundancy in active_trail_nodes

pratyakshs/pgmpy,liquidmetal/pgmpy,ankurankan/pgmpy,pgmpy/pgmpy,yashu-seth/pgmpy,liquidmetal/pgmpy,vivek425ster/pgmpy,vivek425ster/pgmpy,khalibartan/pgmpy,pratyakshs/pgmpy,pgmpy/pgmpy,kislayabhi/pgmpy,kislayabhi/pgmpy,kris-singh/pgmpy,kris-singh/pgmpy,abinashpanda/pgmpy,jhonatanoliveira/pgmpy,abinashpanda/pgmpy,ankurankan/pgmpy,khalibartan/pgmpy,sandeepkrjha/pgmpy,palashahuja/pgmpy,anaviltripathi/pgmpy,anaviltripathi/pgmpy,jhonatanoliveira/pgmpy,palashahuja/pgmpy,sandeepkrjha/pgmpy,yashu-seth/pgmpy