Add property for outputDirectory in create-from-project mojo

Add the "outputDirectory" property, so I can change where this puts the generated archetype code from the command line.

Author: geoffpotter

maven-archetype-plugin/src/main/java/org/apache/maven/archetype/mojos/CreateArchetypeFromProjectMojo.java

@@ -197,7 +197,7 @@ public class CreateArchetypeFromProjectMojo extends AbstractMojo {
     /**
      * The directory where the archetype should be created.
      */
-    @Parameter(defaultValue = "${project.build.directory}/generated-sources/archetype")
+    @Parameter(defaultValue = "${project.build.directory}/generated-sources/archetype", property = "outputDirectory")
     private File outputDirectory;
 
     @Parameter(property = "testMode")