RFR: JDK-8228424: release notes for 12.0.2

[Johan Vos]

Hi Kevin,

Please review https://bugs.openjdk.java.net/browse/JDK-8228424 with webrev
http://cr.openjdk.java.net/~jvos/8228424/webrev.00/ which contains release
notes for 12.0.2

Thanks,

- Johan