fix typo and add sample on how to reuse the produced test jar

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1158601 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/site/apt/usage.apt.vm b/src/site/apt/usage.apt.vm
index 3b10ed6..3ffe2fe 100644
--- a/src/site/apt/usage.apt.vm
+++ b/src/site/apt/usage.apt.vm
@@ -130,7 +130,7 @@
 </project>
 +-----------------+
 
-* How to create a jat containing test classes
+* How to create a jar containing test classes
 
 +-----------------+
 <project>
@@ -157,6 +157,25 @@
 </project>
 +-----------------+
 
+  You can produce a jar which will include your test classes and resources.
+  To reuse this artifact in an other project, you must declare this dependency with classifier test-jar :
+
++-----------------+
+<project>
+  ...
+  <dependencies>
+    <dependency>
+      <groupId>groupId</groupId>
+      <artifactId>artifactId</artifactId>
+      <type>test-jar</type>
+      <version>version</version>
+    </dependency>
+  </dependencies>
+  ...
+</project>
++-----------------+
+
+
 
 
   For full documentation, click {{{plugin-info.html}here}}.