some tweaks

Author: xabbuh

cookbook/form/form_collections.rst

@@ -463,8 +463,8 @@ we talk about next!).
 
 .. caution::
 
-    You have to create **both** ``addTag`` and ``removeTag`` methods, 
-    otherwise the form will still use ``setTag`` even if ``by_reference`` is ``false``. 
+    You have to create **both** ``addTag`` and ``removeTag`` methods,
+    otherwise the form will still use ``setTag`` even if ``by_reference`` is ``false``.
     You'll learn more about the ``removeTag`` method later in this article.
 
 .. sidebar:: Doctrine: Cascading Relations and saving the "Inverse" side
@@ -729,7 +729,7 @@ the relationship between the removed ``Tag`` and ``Task`` object.
     updated (whether you're adding new tags or removing existing tags) on
     each Tag object itself.
 
-.. _cookbook-form-collections-custom-prototype
+.. _cookbook-form-collections-custom-prototype:
 
 Rendering a Custom Prototype
 ----------------------------