Bug fixes in query method. [refs #245]
Bug fixes in query method. [refs #245]

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