JBossPDP isDirectory called should check if the argument is of file pattern

https://issues.jboss.org/browse/JBPAPP-8462 has an exception for the AS7 environment.

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15:51:51,112 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/pdp].[SOAPSAMLXACMLPDPServlet]] (http--127.0.0.1-8080-1) Allocate exception for servlet SOAPSAMLXACMLPDPServlet: java.lang.IllegalArgumentException: URI scheme is not "file"
at java.io.File.<init>(File.java:366) [rt.jar:1.6.0_31]
at org.jboss.security.xacml.core.JBossPDP.isDirectory(JBossPDP.java:590) [jbossxacml-2.0.6.Final.jar:2.0.6.Final]
at org.jboss.security.xacml.core.JBossPDP.addPolicySets(JBossPDP.java:466) [jbossxacml-2.0.6.Final.jar:2.0.6.Final]
at org.jboss.security.xacml.core.JBossPDP.bootstrap(JBossPDP.java:344) [jbossxacml-2.0.6.Final.jar:2.0.6.Final]
at org.jboss.security.xacml.core.JBossPDP.<init>(JBossPDP.java:157) [jbossxacml-2.0.6.Final.jar:2.0.6.Final]
at org.picketlink.identity.federation.core.pdp.SOAPSAMLXACMLPDP.getPDP(SOAPSAMLXACMLPDP.java:126) [picketlink-fed-2.0.2.Final.jar:2.0.2.Final]
at org.picketlink.identity.federation.core.pdp.SOAPSAMLXACMLPDP.<init>(SOAPSAMLXACMLPDP.java:75) [picketlink-fed-2.0.2.Final.jar:2.0.2.Final]
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