add release notes / changelog for using images outside wagtail

CHANGELOG.txt

@@ -10,6 +10,7 @@ Changelog
  * Added decorator syntax for hooks
  * Replaced lxml dependency with html5lib, to simplify installation
  * Added page_unpublished signal
+ * Added mechanism to obtain external URLs to images, at any size
 
  * Fix: Updates to tag fields are now properly committed to the database when publishing directly from the page edit interface
 

docs/core_components/images/using_images_outside_wagtail.rst

@@ -1,3 +1,5 @@
+.. _using_images_outside_wagtail:
+
 ============================
 Using images outside Wagtail
 ============================

docs/releases/0.5.rst

@@ -13,7 +13,7 @@ What's new
 Multiple image uploader
 ~~~~~~~~~~~~~~~~~~~~~~~
 
-The image uploader UI has been improved to allow multiples to be uploaded quickly.
+The image uploader UI has been improved to allow multiple images to be uploaded at once.
 
 
 Image feature detection
@@ -24,6 +24,13 @@ Wagtail can now apply face and feature detection on images using `OpenCV <http:/
 :ref:`image_feature_detection`
 
 
+Using images outside Wagtail
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In normal use, Wagtail will generate resized versions of images at the point that they are referenced on a template, which means that those images are not easily accessible for use outside of Wagtail, such as displaying them on external sites. Wagtail now provides a way to obtain URLs to your images, at any size.
+
+:ref:`using_images_outside_wagtail`
+
 RoutablePage
 ~~~~~~~~~~~~