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/import_smsrc.py

@@ -20,12 +20,11 @@ from datastore import Datastore
 if __name__ == '__main__':
 
 	print("Reading configuration")
-	surveys = configuration.surveys()
 	file_min_age = configuration.read().get('imports', {}).get('file_min_age', 10)
 
 	print("Connecting to database")
 	db = Datastore()
-	db.connect()
+	surveys = db.surveys()
 
 	print("Reading surveys")
 	for survey in surveys: