added install_requires dependencies in setup.py
added install_requires dependencies in setup.py

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