Add code to identify items w/o files nor URL
Add code to identify items w/o files nor URL

-If have neither files nor URL, is not an item really, just a
 description of one.

-Needed to identify where this is the case to know how to format the
 items/show page. Figured ~90% of documents would be either a picture or
 a link, which was correct.

-Of the items with neither:

1.) Most common: the URL was accidentally embedded with the description
    text and needs edited on the admin site.

2.) Next most common: the item is an email or interview, in which case
    the body is stored in ['Item Type Metadata', 'Text'] and just isn't
    accessed by our templates. Need to fix so we check for this type of
    data.

3.) Somewhat amazingly for such a large collection, only one item, #336,
    truly just "describes" an item and needs a picture.

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