Depend on more recent toil

Peter Amstutz · Peter Amstutz · commit ea384b0df00b · 2019-01-18T12:00:46.000-05:00
diff --git a/setup.py b/setup.py
@@ -37,7 +37,7 @@
       extras_require={
           "arvados": ["arvados-cwl-runner"
                       ],
-          "toil": ["toil[all]==3.16.0"
+          "toil": ["toil[all]==3.18.0"
                    ]},
       zip_safe=False
       )
