Suggestion - Support MapMessage format in on_message about stomp.py

[astrasel]

After further development, I realize that this may only have been issue for me because I was accessing an ActiveMQ service that was embedded in another application, and that application developer had not brought over the 'optional' jars (xstream and xpp) that ActiveMQ uses to support the conversion options ('...to-json' and '...to-xml') that are available in the connection method. When these jars were added to the application and I used the to-xml conversion option, my on_message function did indeed get a python dictionary object for the message item and I was able to proceed as suggested above.

Modifying stomp to support case where user does not request the 'to-xml' conversion option, receives a map message and wants to still have it appear as a dictionary type in on_message would appear to be a waste of time, since standard ActiveMQ installs appear to have this 'optional' xtream package by default in any case, so perhaps this issue should be closed.

[jasonrbriggs]

Thanks for the update