Strip url trailing backslash.

rietveld.py

Index: rietveld.py
diff --git a/rietveld.py b/rietveld.py
index d13173b3218cf31cdb21fe096f4b7702161814e2..037640c6abf8e0100f3630f7ef3436b198c0363a 100644
--- a/rietveld.py
+++ b/rietveld.py
@@ -42,7 +42,7 @@ upload.logging.setLevel(logging.WARNING)  # pylint: disable=E1103
 class Rietveld(object):
   """Accesses rietveld."""
   def __init__(self, url, email, password, extra_headers=None):
-    self.url = url
+    self.url = url.rstrip('/')
     # TODO(maruel): It's not awesome but maybe necessary to retrieve the value.
     # It happens when the presubmit check is ran out of process, the cookie
     # needed to be recreated from the credentials. Instead, it should pass the