correct verify_SSL (#33)

Correct field name is 'verify_SSL'. Currently test.py reports 'Could not contact the server.' because of this mistype.

licensing/internal.py

@@ -124,7 +124,7 @@ def send_request(method, params):
             params: a dictionary of parameters
         """
 
-        if HelperMethods.verify_SLL:
+        if HelperMethods.verify_SSL:
             return urllib.request.urlopen(HelperMethods.server_address + method, \
                                       urllib.parse.urlencode(params)\
                                       .encode("utf-8")).read().decode("utf-8")