modified LGCPD.__str__ and fixed some bugs
modified LGCPD.__str__ and fixed some bugs

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