Updated UPGRADING file

git-svn-id: svn://svn.silverstripe.com/silverstripe/open/phpinstaller/trunk@44663 467b73ca-7a2a-4603-9d3b-597d59a354a9

UPGRADING

@@ -1,6 +1,20 @@
-To upgrade your installation of SilverStripe, simply copy the
-sapphire, cms & jsparty folders overtop of your existing installation.
-Then flush the cache and rebuild the database (db/build?flush=1).
+Usually upgrading your SilverStripe installation just means overwriting files
+and updating your database-schema.
 
-If there are any special notes on upgrading to a particular version,
-these will be documented here.
+  - Backup your database
+  - Backup your webroot
+  - Download the new release and uncompress it to a temporary folder
+  - With these folders: cms, sapphire, jsparty and auth_openid
+      - Delete your existing folders
+      - Extract and replace folders from your download (leave modules
+        and your custom directories alone)
+      - Moving your current folders (rather than installing on top) means
+        you can undo the installation, and ensures if the new release has no
+        longer contains some files, these files won’t be left behind, which otherwise
+        could cause bugs.
+      - Visit http://your.silverstripe.site/db/build?flush=1 (This adds new
+        fields/tables to the database, and empties your template cache)
+  - Check if any modules (e.g. blog or forum) in your installation are compatible
+    and need to be upgraded as well
+  - Check if you need to adapt your code to changed APIs, see
+    http://doc.silverstripe.com/doku.php?id=upgrading