[jboss-as7-dev] Extending AS 7 and testing subsystem parsing

There is a guide to extending AS 7 which currently lives in the Admin Guide https://docs.jboss.org/author/display/AS7/Admin+Guide#AdminGuide-Extendin... (although I've seen mention of moving it somewhere else). The guide has a maven archetype to set up a skeleton project, this will be deployed later today. The archetype contains tests for parsing the model, most of this was stolen from other places but what I think it is new in getting different things together. So we can parse the model and install in the controller, making sure that the proper operations get called resulting in a real model in the controller and services getting installed without the need for any fancy module setup. It is still a bit basic but I think it would be a good idea to copy the utility classes into the AS 7 codebase somewhere (the question is where) so that we can evolve them to give better functionality in the archetype and of course to our own subsystem testing. The example code using this stuff can be found at https://docs.jboss.org/author/download/attachments/5439694/acme-subsystem.... The main thing I can think of that is missing at the moment is to be able to preinitialize the controller with model elements and services that should be there before your extension is deployed.