Add and clarify manual release process steps

[henrikingo]

• Clarify and separate the two svn repos https://dist.apache.org/repos/dist/dev/incubator/otava https://dist.apache.org/repos/dist/release/incubator/otava

• Use test.pypi.org earlier

• Link to otava.apache.org/download for downloadsin the final announcement

[henrikingo]

Follow-up activities to the release:

• This PR: Several additions and clarifications to docs/RELEASE.md
• Unless someone objects, I will move the previous releases 0.6.0, 0.7.0 and 0.7.1 from https://dist.apache.org/repos/dist/dev/incubator/otava/ to https://dist.apache.org/repos/dist/release/incubator/otava/
• Website, one remaining fix: The "all releases" part of https://otava.apache.org/docs/download should point to URLs that start with archive.apache.org or in any case never to https://dist.apache.org/repos/dist/dev/incubator/otava/
• IMO docker builds should also be published somewhere before voting. Proposal beloiw.

The above should fix everything that came up during the voting and review on the Incubator list. But one last comment is that this process has way too many manual steps. It is almost 2 days of work (for a first timer anyway) and very error prone due to the complexity. So I would like to propose as follow-up work that we automate a large part of this in Github CI. Specifically, the creation of source tar, pypi tar and whl, and docker image should be running in CI anyway. If the CI detects that user pushed a tag that has the form x.y.z-incubating-rcN then the resulting artifacts will also be attached to the result of the workflow.

The release managers job is then just to download and carefully test and review these files, sign them, upload to dist.apache.org/.../dev/ and start the voting.

[justinmclean]

It's probably better to use an SVN move command to transfer the RC from the dive to the dist area. If you do this, there's no need to check it out, and you're 100% that the RC you have voted on is the release.

[henrikingo]

Thanks. I wasn't sure if these are the same repo or independent/ if this is possible. Certainly makes sense if it is.

[dave2wave]

While it may be better to use SVN move. SVN import is also effective.

On another note. The new Apache Trusted Release platform is about to be ready for Alpha3 and this will automate many of the release steps.

[henrikingo]

On another note. The new Apache Trusted Release platform is about to be ready for Alpha3 and this will automate many of the release steps.

Glad to hear. I would have filed a ticket to automate most of this otherwise. Happy to wait for a centralized solution.

[dave2wave]

Next Otava release let's use ATR.

I believe all is fixed or acknowledged properly.