It appears production signing service needs a valid file extension so provide one.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1627393 13f79535-47bb-0310-9956-ffa450edef68
Bump up the buffer size since the installer is getting close to 10MB.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1627394 13f79535-47bb-0310-9956-ffa450edef68