Predictable release dates

[Marcus Hirt]

Hi all,

Mario and I have been discussing our release dates, and Mario suggested
that we try to track the release dates with the JDK CPU release dates.

JDK releases are in March and September. CPU releases (and thus our
targets) are in Jan/Apr/Jul/Oct.

I'm not convinced we need a release every 3 months, but I do believe having
a date that tracks with other OpenJDK release dates may be helpful for
things like vulnerability embargo dates. It also gives us some time to
react to new releases of the JDK. 1 month if we're fast, and another
opportunity 3 months later if we miss it.

For JMC 8 this means that we could do a source release 2021-01-19, giving
us time to complete Rules 2.0 properly, and even allow some time for
feedback, not to mention have a sane ramp-down of the project.

Here are some suggested milestone dates:

2020-11-23 - Rampdown Start (RDS)
2020-12-18 - Rampdown Phase 2 (RDP2)
2021-01-19 - Source Release

(See: https://wiki.openjdk.java.net/display/jmc/JMC+Development+Process+FAQ)

What do you think?

Kind regards,
Marcus