title: mvn release:perform fails because pom file is not at root of repository
body: <p>I am trying to execute <code>mvn release:perform</code>, but the command assumes that the pom file is at the root of the repository.  Is there a system property or preference that I can set to override the default?</p>
  
  <p>The call to <code>mvn release:prepare</code> seems to have succeeded as all the release artifacts are sitting in the target directory and the repository is properly tagged.</p>
  
  <p>In case it matters, this is a git project.</p>
  
  <hr>
  
  <p><strong>EDIT</strong> Here is what I did:</p>
  
  <pre><code>cd /path/to/git/root/path/to/mvn/project
  mvn -DdevelopmentVersion=1.2.0-SNAPSHOT -DreleaseVersion=1.1.0 release:prepare
  ...enter correct passphrase and choose all default options...
  mvn release:perform
  </code></pre>
  
  <p>And then cloning the remote repo in the <code>target/checkout</code> directory and after some churning and pushing to the remote git repo, the following error happens:</p>
  
  <pre><code>[ERROR]   
  [ERROR]   The project  (/path/to/git/root/path/to/mvn/project/target/checkout/pom.xml) has 1 error
  [ERROR]     Non-readable POM /path/to/git/root/path/to/mvn/project/target/checkout/pom.xml: /path/to/git/root/path/to/mvn/project/target/checkout/pom.xml (No such file or directory)
  </code></pre>
  
  <p>So, maven is looking for the pom file in the root of the <code>target/checkout</code> directory, which is not where it is located.</p>