Implement Api.has_credentials()

This patch allows the API object to report whether or not authentication
credentials was supplied upon object instantiation.

Releases version 6.4.0.

productstatus/api.py

@@ -89,6 +89,13 @@ def delete_event_listener(self):
         del self._event_listener
         self._event_listener = None
 
+    def has_credentials(self):
+        """!
+        @brief Returns True if a username and API key was supplied with the API
+        object constructor, False otherwise.
+        """
+        return self._session.auth is not None
+
     def _do_request(self, method, *args, **kwargs):
         """
         Run a request through the requests API. This function wraps

setup.py

@@ -6,7 +6,7 @@
     'author': 'MET Norway',
     'url': 'https://github.com/metno/python-productstatus-client',
     'download_url': 'https://github.com/metno/python-productstatus-client',
-    'version': '6.3.0',
+    'version': '6.4.0',
     'install_requires': [
         'nose==1.3.7',
         'requests==2.9.1',