title: How to use properly mvn release:prepare?
body: <p>I try this command (with <code>dryrun</code> to test) on my Maven project :</p>
  <pre><code>mvn release:clean release:prepare -DdryRun=true -DgenerateBackupPoms=false -Dtag=solocal-refentreprive-2.1-RC02 -DreleaseVersion=2.1-RC02 -DdevelopmentVersion=2.1-SNAPSHOT
  </code></pre>
  <p>At the end, the build is success, but I have (in my commit) many <code>pom.next</code> / <code>pom.tag</code> and <code>pom.backUp</code>...</p>
  <p>I don't when then (<code>-DgenerateBackupPoms=false</code>), if I use without <code>dryrun</code>. I don't want push this pom...</p>