Merge update/docs-slash

- Included tip regarding the starting slash.

Author: Rik Bos

README.md

@@ -37,7 +37,7 @@ jQuery('p').css('color', 'red')
 - **Contents :**
   The HTML or Javascript to embed.
 - **External File :**
-  The path to the HTML or JavaScript file you want to add. The root is the theme folder. Will override the Contents section if used.
+  The path to the HTML or JavaScript file you want to add. The root is the theme folder. Will override the Contents section if used. With the newly added "/p/" native deeplinks, you may want to start your file path with a "/" to prevent any 404s caused by this deeplink. 
 - **On click microflow :**
   The microflow which should be executed on click. This can be used to, for example, show a page when the snippet is being clicked.
 - **Documentation :**