Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56638
When using ELProcessor.defineFunction(String,String,String,String) and no function name is specified, use the method name as the function name as required by the specification.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1603576 13f79535-47bb-0310-9956-ffa450edef68