add MANIFEST.in
add MANIFEST.in

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