This is a feature and bugfix release. * Implement "once" and "lazy" bridge start types. * Add support for $SYS/broker/clients/maximum and $SYS/broker/clients/active topics. * Add support for $SYS messages/byte per second received/sent topics. * Updated mosquitto man page - $SYS hierarchy and signal support were out of date. * Auto generated pub/sub client ids now include the hostname. * Tool for dumping persistent DB contents is available in src/db_dump. It isn't installed by default. * Enforce topic length checks in client library. * Add new return type `MOSQ_ERR_ERRNO` to indicate that the errno variable should be checked for the real error code. * Add support for `connection_messages` config option. * mosquitto_sub will now refuse to run if the -c option (disable clean session) is given and no client id is provided. * mosquitto_pub now gives more useful error messages on invalid input or other error conditions. * Fix Python `will_set()` true/True typo. * Fix messages to topic `a/b` incorrectly matching on a subscription `a` if another subscription `a/#` exists.