QPID-6006: [Java Broker] UI to expose attribute defaults during create and edit workflows

* Metadata service now used to discover the attributes for each category instance type.
* Create/edit dialogues now have promptMessages to provide a fuller description of the field's purpose
* If the attribute has a default, the default is interpolated into the promptMessage in a standard way.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1618373 13f79535-47bb-0310-9956-ffa450edef68
QPID-6000 : [Java Broker] [Java Client] add the ability to configure automatic message compression

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1618375 13f79535-47bb-0310-9956-ffa450edef68