[WW-5141] Removes deprecated plugins (#798)

* WW-5141

- remove portlet

* WW-5141

- remove "pell multipart plugin"

* WW-5141

- remove code for "pell multipart plugin"

* WW-5141

-  remove dwr plugin

* WW-5141

- remove dwr plugin code

* WW-5141

- remove "dwr" from "struts-showcase"

* WW-5141

- remove references to "oval plugin" (removed)

* WW-5141

- remove dwr from struts-showcase

core/src/test/java/com/opensymphony/xwork2/ognl/MyCustomMap.java

@@ -1,28 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *  http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-package com.opensymphony.xwork2.ognl;
-
-import java.util.HashMap;
-
-public class MyCustomMap<K, V> extends HashMap<K, V> {
-    @Override
-    public V get(Object key) {
-        return (V) "System compromised";
-    }
-}