Merge pull request #1379 from brentashley/develop

Add step to move existing core extensions to new folder
diff --git a/user_guide_src/source/installation/upgrade_200.rst b/user_guide_src/source/installation/upgrade_200.rst
index b39f4fd..29f44bd 100644
--- a/user_guide_src/source/installation/upgrade_200.rst
+++ b/user_guide_src/source/installation/upgrade_200.rst
@@ -87,7 +87,14 @@
 convention. Please update extended libraries to call
 parent::\__construct().
 
-Step 8: Update your user guide
+Step 8: Move any core extensions to application/core
+====================================================
+
+Any extensions to core classes (e.g. MY_Controller.php) in your
+application/libraries folder must be moved to the new 
+application/core folder.
+
+Step 9: Update your user guide
 ==============================
 
 Please replace your local copy of the user guide with the new version,