Add support for catalogs

[Stephan Wienczny]

Please add support for jax-ws-catalog.xml

I've got wsdl files that reference remote xsds. If you don't want to download these files for every build you need to use a jax-ws-catalog.xml that maps the remote urls to local ones so you can download the xsd once.
The jax-ws-catalog.xml should be added to META-INF/jax-ws-catalog.xml inside the artifact, too.

The ant-task supports catalogs by using the -catalog option.

Maybe a wsdl download task that

• downloads the *.wsdl using a given url
• downloads all referenced *.xsd
• builds a jax-ws-catalog.xml
  would be useful, too