RFR: JDK-8237490: [macos] Add support notarizing jpackage app-image and dmg

[Andy Herrick]

Please review the fix to issue [1] at [2].

This change enables notarization on Mac for dmg images and app-image zip 
files.

/Andy

[1]: https://bugs.openjdk.java.net/browse/JDK-8237490

[2]: http://cr.openjdk.java.net/~herrick/8237490