Revert "MNG-5552 made classifier part of MavenProject.artifactMap key"

This reverts commit f35698c790da5329590d1ceba0502c02f942efdf.

There are plugins that rely on the broken behaviour and I don't have the
time to fix this in backwards compatible way right now.

http://markmail.org/message/gjfuofw5gpsr5yxz

Signed-off-by: Igor Fedorenko <ifedorenko@apache.org>
Add a test for parsing the thread configuration with the core multiplier
[maven-release-plugin] prepare release maven-3.2.1
[maven-release-plugin] prepare for next development iteration
Add missing header
Move the POMs back the 3.2.1-SNAPSHOT
[maven-release-plugin] prepare release maven-3.2.1
[maven-release-plugin] prepare for next development iteration
Add a provisional marker to the Builder interface and add a bit of javadoc.
Turn on rat by default so that we can move toward any standard build passing being a viable release candidate. Anything important that may block a release
should be run as a standard part of the release. It's an anti-pattern, and very annoying, to have something required only be run during the release process.
Small improvement on comments in formatTimestamp.