vocabulary fix

ecplugin.py

@@ -17,7 +17,7 @@
 
 
 class MBOXImportCommand(Command):
-    """Import files using the Unix mail box format into an cubicweb application.
-    The application must use the email package.
+    """Import files using the Unix mail box format into an cubicweb instance.
+    The instance must use the email package.
 
     <pyro id>
@@ -22,6 +22,6 @@
 
     <pyro id>
-      pyro identifier of the application where emails have to be imported.
+      pyro identifier of the instance where emails have to be imported.
 
     <mbox file>
       path to a file using the Unix MBOX format. If "-" is given, stdin is read.