add servlet-mapping path style support for include tag in config file

I wish struts2 can do this like spring configuration "classpath*:resources/applicationContext-*.xml",it make more easy for modularization and plugin.

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<constant name="struts.devMode" value="true" />
<constant name="struts.i18n.encoding" value="UTF-8" />
<include file="resources/struts-*.xml" />
</struts>