Integration test modules are deployed during a release

When trying to release 0.3.6, I discovered that the nexus-staging-maven-plugin plugin is used for deployment (to a Maven Central staging repository), but this does not respect nor use the configuration of the maven-deploy-plugin that normally prevents deployment.

So, either we deploy all of our integration tests to Maven Central, or we somehow change our deployment mechanism.

For 0.3.6, I'm going to altogether remove the integration tests (see DBZ-151) from the 0.3.x branch. They are still in the master branch, and so we still need to figure out what to do with the 0.4 release.