title: Maven checkstyle not running as part of build
body: <p>I'm totally lost as to why not.  Structure is like this:</p>
  
  <p>using mvn checkstyle:check creates the reports (I have identical settings in reporting section) but build treats the plugin like it doesn't exist.  If I change the checkstyle version, it doesn't download it, etc.  Essentially it treats this config as invisible.</p>
  
  <pre><code>&lt;build&gt;
     &lt;pluginManagement&gt;
           &lt;plugins&gt;
              &lt;plugin&gt;
                &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
                &lt;artifactId&gt;maven-checkstyle-plugin&lt;/artifactId&gt;
                &lt;version&gt;2.13&lt;/version&gt;
  
                &lt;configuration&gt;
                  &lt;configLocation&gt;checkstyle.xml&lt;/configLocation&gt;
                  &lt;suppressionsLocation&gt;checkstyle-suppressions.xml&lt;/suppressionsLocation&gt;
                  &lt;maxAllowedViolations&gt;2500&lt;/maxAllowedViolations&gt;
                  &lt;consoleOutput&gt;true&lt;/consoleOutput&gt;
                  &lt;failsOnError&gt;true&lt;/failsOnError&gt;
                  &lt;failOnViolation&gt;true&lt;/failOnViolation&gt;
                &lt;/configuration&gt;
  
                &lt;executions&gt;
                  &lt;execution&gt;
                    &lt;id&gt;checkstyle&lt;/id&gt;
                    &lt;goals&gt;
                      &lt;goal&gt;check&lt;/goal&gt;
                    &lt;/goals&gt;
                    &lt;configuration&gt;
  
                      &lt;encoding&gt;UTF-8&lt;/encoding&gt;
                      &lt;consoleOutput&gt;true&lt;/consoleOutput&gt;
                      &lt;failsOnError&gt;true&lt;/failsOnError&gt;
                      &lt;failOnViolation&gt;true&lt;/failOnViolation&gt;
                    &lt;/configuration&gt;
                  &lt;/execution&gt;
                &lt;/executions&gt;
              &lt;/plugin&gt;
  .....
  &lt;/plugins&gt;
  &lt;/pluginManagement&gt;
  &lt;/build&gt;
  </code></pre>