Policies for implementing XACML RBAC for reader, writer and admin roles.
Fixed URIs for policy sets and rules and subject role ID.
Add fcrepo namespace, fix fcrepo URIs
Fix Policy Set Combining algorithm;  misc typos
Change SubjectAttributeDesignator data type to string
Merge pull request #8 from sprater/xacml-rbac-policies

Policies for implementing XACML RBAC for reader, writer and admin roles.