Wildcards in topic names

[Adamovich Aliaksandr <adamovichat@gmail.com>]

Hello!

I have some proposal to standard.

According to MQTT 5.0 i must publish an empty message to remove existing 
retain message from the broker storage.

I have a lot of retain messages with deep topics hierarchy like 'a/b/1', 
'a/b/2'. I don't have any way to easily remove all of them except 
enumerating.

The possible solution is to allow wildards in message topic like 'a/#', 
when message published without payload and retain bit. Broker must 
remove all matched retain messages.


Aliaksandr Adamovich