AWA blog plugin fails to serve an image when it is stored in the storage directory

[stcarrez]

When an image is big it can be stored in the storage directory instead of the database (this is configurable).

Then, when the image is referenced from a blog article, the blog image servlet does not load the image content.
The image is therefore not served and we get a 404 error.

There is no issue if the image was stored in the database.