Testing release candidates

[Enrico Olivelli <eo...@gmail.com>]

Hello,
During the VOTE for 4.10.0 Karan asked how to test and RC.

Let me give an example of tests:
- check checksums and signatures
- try to build sources
- try to run a server/cluster from the built sources
- try to use bin/bookkeeper and/or bin/bkcl
- try to use the convenience binaries
- try to use the staged Maven artifacts
- check for license stuff, in the convenience binaries and sources
- validate that the git tag is consistent with the staged sources
- check release notes
- test background compatibility
- test upgrades of the server/client
- check docs, especially for new features

In my opinion the most important checks for an user/developer are about
testing the features you are using in your downstream project.
Take care that if you upgrade your project with the new version of
BookKeeper it runs fine and hopefully "better".
Test for performance (whatever it means for your project), ensure that
there are no regressions.

Check for new cool features and .if have time give them a try.

Please report what you did, the OS and the Java version.
Please report any kind of issues, or any suspect of misbehaviour.

BookKeeper is a fundamental piece of many other higher level systems we
must be very conservative and prevent regressions of any type.

Best regards
Enrico