When generating the download urls for images in export_view, the '/' characters in page titles don't seem to be escaped correctly. Even when manually escaping this character, the image cannot be downloaded using the resulting url.

Steps to reproduce:

1. Create a page called 'a/b'
2. Attach an image called 'test.jpg' to it.
3. Call the storage to view conversion service (fix the page ID):
   POST jens-k15t.atlassian.net/wiki/rest/api/contentbody/convert/export_view

   {
       "value" : "<p><ac:image ac:height=\"250\"><ri:attachment ri:filename=\"test.jpg\" /></ac:image></p>",
       "representation" : "storage",
     	"content":{"id":"22413329"}
   }
   

4. Returned HTML:

   <p>
       <span class="confluence-embedded-file-wrapper confluence-embedded-manual-size">
           <img class="confluence-embedded-image" height="250" src="https://jens-k15t.atlassian.net/wiki/download/attachments/embedded-page/INT/a/b/test.jpg?api=v2">
       </span>
   </p>
   

5. The image can not be loaded using this url, check out the part with the filename: .../embedded-page/INT/a/b/test.jpg