INT-3418: xsd-1.0 -> 2.0
INT-3418: xsd-2.0 -> 2.1
INT-3418: xsd-2.1 -> 2.2
INT-3418: xsd-2.2 -> 3.0
INT-3418: xsd-3.0 -> 4.0
INT-3418: xsd-4.0 -> 4.1
INT-3418: Final Phase: Cleanup
INT-3418: use versioned XSDs for XSD import