Added plot_generator.py to generate example gallery.
Added plot_generator.py to generate example gallery.

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