heni/rem — pull request #2 by znick (2013-06-03 12:13:56+00:00)
Title: Rotate TagLogger only if self.db_file exists.

If self.Open(self.db_file) fails after rename at least once (e.g. because of not enough space), there is no chance to recreate self.db_file in the future (and all scheduler.RollBackup() fails because of it).

So, lets rename only if self.db_file exists.