Initial XACML branch

Only config changed. 
Need to add dependencies to:
Fcrepo4 XACML Authorization Delegate: https://github.com/fcrepo4/fcrepo-module-auth-xacml
JBOSS XACML library: http://grepcode.com/snapshot/repository.jboss.org/nexus/content/repositories/releases/org.jboss.security/jboss-xacml/2.0.8.Final