add report port to rng step

[gimsieke]

In order to enable validation message reporting, the default p:validate-with-relax-ng step needs a report port, just like p:validate-with-schematron.

This one uses a p:exec which invokes 'java': http://www.oxygenxml.com/pipermail/oxygen-user/2010-July/003221.html

Is that portable enough?

What is the canonical way to bind custom pipeline types to java classes, so we can distribute just the class file?

[gimsieke]

Let’s see if we can invoke p:exec of java in a packaged Windows application that brings its own JVM and where there’s no 'java' binary in the path or even installed. I think we’ll have to implement a Calabash extension for that. Florent has given an example here: http://fgeorges.blogspot.com/2011/09/writing-extension-step-for-calabash-to.html

[gimsieke]

Also a useful link for Calabash extension development: http://lists.w3.org/Archives/Public/xproc-dev/2011Jul/0021.html