Fix a typo (#557)

Author: lesv

appengine/helloworld-new-plugins/pom.xml

@@ -57,17 +57,13 @@ Copyright 2015 Google Inc.
         <configuration>
           <!-- dev appserver configuration (standard environment only) -->
           <!--
-          <devserver.host>127.0.0.1</devserver.port>
+          <devserver.host>127.0.0.1</devserver.host>
           <devserver.port>8080</devserver.port>
           -->
           <!-- staging configuration (standard/flex-compat environment only) -->
           <!--
           <stage.enableJarSplitting>true</stage.enableJarSplitting>
           -->
-          <!-- staging configuration (flexible environment only) -->
-          <!--
-          <stage.artifact>target/some-customer-artifact.jar</stage.artifact>
-          -->
           <!-- deploy configuration -->
           <deploy.promote>true</deploy.promote>
           <deploy.stopPreviousVersion>true</deploy.stopPreviousVersion>