Added ispublic node property (alias of publicread)

src/main/java/it/inaf/oats/vospace/datamodel/NodeProperties.java

@@ -26,6 +26,7 @@ public abstract class NodeProperties {
     public static final String LENGTH_URI = "ivo://ivoa.net/vospace/core#length";      // the length or size of a resource      
     public static final String MODIFICATION_TIME_URI = "ivo://ivoa.net/vospace/core#mtime";       // the data modification time    
     public static final String PUBLIC_READ_URI = "ivo://ivoa.net/vospace/core#publicread";  // whether this resource is world readable
+    public static final String IS_PUBLIC_URI = "ivo://ivoa.net/vospace/core#ispublic";  // alias of publicread used by CADC
     public static final String PUBLISHER_URI = "ivo://ivoa.net/vospace/core#publisher";   // an entity responsible for making the resource available
     public static final String QUOTA_URI = "ivo://ivoa.net/vospace/core#quota";       // the value of a system quota on the resource   
     public static final String RELATED_RESOURCE_URI = "ivo://ivoa.net/vospace/core#relation";    // a related resource