SEC-436: Add hashCode() methods.

core/src/main/java/org/acegisecurity/acls/domain/BasePermission.java

@@ -161,4 +161,8 @@ public final class BasePermission implements Permission {
     public String toString() {
         return "BasePermission[" + getPattern() + "=" + mask + "]";
     }
+    
+	public int hashCode() {
+		return this.mask;
+	}
 }

core/src/main/java/org/acegisecurity/acls/domain/CumulativePermission.java

@@ -56,8 +56,12 @@ public class CumulativePermission implements Permission {
 
         return (this.mask == rhs.getMask());
     }
+    
+	public int hashCode() {
+		return this.mask;
+	}
 
-    public int getMask() {
+	public int getMask() {
         return this.mask;
     }