If Molecule contains a ~ load it as SMARTS (#71)

Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Reviewed-on: enviPath/enviPy#71

utilities/chem.py

@@ -682,6 +682,9 @@ class IndigoUtils(object):
         i.setOption("render-image-size", width, height)
         i.setOption("render-bond-line-width", 2.0)
 
+        if '~' in mol_data:
+            mol = i.loadSmarts(mol_data)
+        else:
             mol = i.loadMolecule(mol_data)
 
         if len(functional_groups.keys()) > 0: