Add function to retrieve survey configurations from DB.

As the survey definitions will no longer be stored in files
under etc/surveys/ but directly on the database, this
function replaces configuration.surveys()

bin/configuration.py

@@ -55,6 +55,10 @@ def files (globspec = None, include_archived = False):
 	quickly and temporarily “disabling” a survey configuration by renaming
 	the relevant file.
 	"""
+
+	print("This method is obsolete")
+	return
+
 	tuples = []
 
 	if globspec is None: