Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56568
Enable any HTTP method to be used to request a JSP page that has the isErrorPage page directive set to true.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1620596 13f79535-47bb-0310-9956-ffa450edef68