Add remark about breaking change to ASP009 docs.

JohanLarsson · JohanLarsson · commit 2de08503b62a · 2018-12-31T13:53:13.000+01:00
diff --git a/documentation/ASP009.md b/documentation/ASP009.md
@@ -29,6 +29,7 @@
 ## Description
 
 Use kebab-cased urls.
+Note that this is a breaking change.
 
 ## Motivation
 
