An EntityResolver implementation which attempts to resolve
various systemId URLs to local classpath lookups
Any systemId URL beginning with http://jboss.com/products/seam/ is
searched for as a classpath resource in the classloader which loaded the
Hibernate classes.
Any systemId URL using classpath as the scheme (i.e.
Uses a brute force O(n^4) algorithm to discover an acceptable
order for partially ordered elements where the transitivity
of the ordering is not known in advance.