transfer script for XR to Peppol BIS Billing NRS

• add script
• add ant target

requirements:

based on src/validation/schematron/ubl/XRechnung-UBL-validation.sch

• exclude title
• exclude include
• exclude <phase>
• include only pattern "ubl-pattern", but remove pattern id
• include only those global variables from src/validation/schematron/common.sch that are not blacklisted in xr-variables-list.xml (i.e. only those that will be referenced in the transformation result)
• asserts:
  • exclude those with @exclude="true" (listed in xr-rules-list.xml) from transformation
  • replace XR assert/@id with Peppol Id (a:assert/@key to a:assert/@id in xr-rules-list.xml)
  • translate assert texts ((dummy) translations in xr-rules-list.xml)
• rules:
  • add supplier and customer country check to @context path
  • include rules only if they contain assertions
  • include only variables that are referenced in included assertions