log message on not found author

cps/db.py

@@ -790,6 +790,7 @@ class CalibreDB():
                 results = self.session.query(Authors).filter(Authors.sort == auth.lstrip().strip()).all()
                 # ToDo: How to handle not found author name
                 if not len(results):
+                    log.error("Author {} not found to display name in right order".format(auth))
                     error = True
                     break
                 for r in results: