fixes in add_edge in NaiveBayes
fixes in add_edge in NaiveBayes

abinashpanda/pgmpy,khalibartan/pgmpy,abinashpanda/pgmpy,sandeepkrjha/pgmpy,anaviltripathi/pgmpy,kris-singh/pgmpy,pgmpy/pgmpy,ankurankan/pgmpy,liquidmetal/pgmpy,kris-singh/pgmpy,khalibartan/pgmpy,jhonatanoliveira/pgmpy,liquidmetal/pgmpy,sandeepkrjha/pgmpy,pgmpy/pgmpy,ankurankan/pgmpy,anaviltripathi/pgmpy,jhonatanoliveira/pgmpy