fix for PolicyIteration's policy0 code unit test
fix for PolicyIteration's policy0 code unit test

McCabeJM/pymdptoolbox,silgon/pymdptoolbox,McCabeJM/pymdptoolbox,sawcordwell/pymdptoolbox,yasserglez/pymdptoolbox,silgon/pymdptoolbox,sawcordwell/pymdptoolbox,yasserglez/pymdptoolbox