Add the other echo endpoints

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1603271 13f79535-47bb-0310-9956-ffa450edef68
Enable the async echo endpoint

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1603274 13f79535-47bb-0310-9956-ffa450edef68