Renaming Inference module to inference module in doctests.
Renaming Inference module to inference module in doctests.

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