Downgrade log rotation detection message to DEBUG level from INFO. Closes: gh-129

This message useful only when debugging problems so it is more reasonable
to have it suppressed otherwise

server/filter.py

@@ -550,7 +550,7 @@ class FileContainer:
 		stats = os.fstat(self.__handler.fileno())
 		# Compare hash and inode
 		if self.__hash != myHash or self.__ino != stats.st_ino:
-			logSys.info("Log rotation detected for %s" % self.__filename)
+			logSys.debug("Log rotation detected for %s" % self.__filename)
 			self.__hash = myHash
 			self.__ino = stats.st_ino
 			self.__pos = 0