[sandbox-9-jake] Review Request 8080531 - fix ant-javafx ant tasks

[Danno Ferrin]

Kevin, Chris, Dmitry
    Because of the way resources are being handled in current revs of Jake we need to pull the main ant task classes back into ant-javafx and not deploy them into the main packager module.  Properly exported in module-info.java all of the other classes are just fine.  It touches the build.gradle hence the need for Kevin's vote.

This patch adds the notion of a set of classes to exclude from the generated module.  FXPackager then excludes the ant classes from the module and makes sure those are the only classes included in ant-javafx.jar.  Fairly straightforward (for once).  

webrev: http://cr.openjdk.java.net/~shemnon/8080531/webrev.05/ <http://cr.openjdk.java.net/~shemnon/8080531/webrev.05/>
supporting jira: https://bugs.openjdk.java.net/browse/JDK-8080531 <https://bugs.openjdk.java.net/browse/JDK-8080531>