Added sbt build script to project

Adding a sbt build script allows this project to be built as part of a
source dependency
Fixed compiler warning when using postfix operator
Added simple way to set MessageConsumer callback

Added listen method to MyConsumer class that takes Message => Unit and
automatically creates new MessageListener with onMessage method which
invokes provided function
Added method to Message implicit to convert to bytes
Updated resolvers setting to fix issue with resolver not checking JBoss repo
Merge pull request #1 from nugend/master

Small Fixes and SBT compatibility