http: Fix superclass method access.

Actually access direct superclass. Too bad base class is not a new-style
class...

caucase/http.py

@@ -77,7 +77,7 @@ class CaucaseSSLWSGIRequestHandler(CaucaseWSGIRequestHandler):
   """
   ssl_client_cert_serial = '-'
   def get_environ(self):
-    environ = WSGIRequestHandler.get_environ(self)
+    environ = CaucaseWSGIRequestHandler.get_environ(self)
     client_cert_der = self.request.getpeercert(binary_form=True)
     if client_cert_der is not None:
       cert = x509.load_der_x509_certificate(