Uploading new banner image leaves html snippet unchanged

[Michael Nelson]

When uploading a new image for an exhibit, the banner_url is updated correctly to the newly uploaded image, but the html snippet still contains the reference to the old image, unless manually updated (see below [1])

It would be great to automatically update any refs within the html snippet, as USC will only display the image defined in the banner_url (for security reasons).

[1] An example
{{{
    {
        ...,
        "banner_url": "http://software-center.ubuntu.com/site_media/exhibits/2012/08/Humble-Bundle_banner_w-button_AW_1.png",
        "html": "<div style=\"background-color: #000000; width:1680px; height:200px;\">\r\n <div style=\"background: url('/site_media/exhibits/2012/08/Humble-Bundle_banner_w-button_AW.png') top left no-repeat; width:700px; height:200px;\"></div>\r\n</div>",
        ...,
    },
}}}

[John Pugh (jpugh)]

I'm thinking that it would be better to allow over writing of the image vs automatically renaming the image. We explicitly uploaded a file name - the system *should* not change what is uploaded.

The problem is that the "system" changed the uploaded file name and the html snippet showed the image since the original image existed.

Another solution is to allow selecting an existing file.