updated some docstrings in BayesinaModel
updated some docstrings in BayesinaModel

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