Require snappy_manifolds 1.4 because of the RibbonLinks census

Author: NathanDunfield

setup.py

@@ -206,7 +206,7 @@ def run(self):
 install_requires = ['decorator',
                     'networkx',
                     'packaging',
-                    'snappy_manifolds>=1.3',
+                    'snappy_manifolds>=1.4',
                     'knot_floer_homology>=1.2.2']
 
 setup( name = 'spherogram',