Add Rest API for Meta Data Image

[rhysgodfrey]

Add a REST API that allows the image selected by the Meta Data plugin based on ContentId and ContentTypeId.

Usage:

/api.ashx/v2/content/meta-data/image/{contentTypeId}/{contentId}.json (or .xml)

Returns the URL of the image found, or an empty string if no image found.

If ContentTypeId or ContentId is in an incorrect format an error response will be returned with the reason in the Errors collection.

Example Response:

{  
   "meta-data-image":"http://www.example.org/images/some-image.png",
   "Errors":[  

   ]
}