Added JDAPermissionManager#savePermissionNode() to be able to save nodes.

We cant remove nodes.

Author: RealMangorage

src/main/java/org/mangorage/mangobotcore/api/jda/permission/v1/JDAPermissionManager.java

@@ -23,4 +23,9 @@ public static JDAPermissionManager create(DatabaseHandler<String, JDAPermissionN
     public JDAPermissionNode getPermissionNode(String id) {
         return permissionNodes.computeIfAbsent(id, JDAPermissionNode::create);
     }
+
+    public void savePermissionNode(JDAPermissionNode node) {
+        databaseHandler.saveEntity(node);
+    }
+
 }