RFR : 8180946: Use Mercurial tags to identify GA builds

[Seán Coffey]

I'd like to propose a jcheck patch for the proposed tag changes which 
will help identify GA JDK builds [1]

webrev : http://cr.openjdk.java.net/~coffeys/webrev.8180946/webrev/
JBS: https://bugs.openjdk.java.net/browse/JDK-8180946

[1] http://mail.openjdk.java.net/pipermail/jdk-dev/2018-October/002094.html

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Regards,
Sean.