Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=54964
Enable tag plug-ins to be packaged with a web application.
Patch by Sheldon Shao.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1486891 13f79535-47bb-0310-9956-ffa450edef68