Add a file upload field for Documentation of Relationship

[waldoj]

Right now it's just a text input field. JSON Schema has no concept of files. For this prototype, we need this to look like a file input. I suspect that this is best done via the onBeforeRender function. However we do it, the idea is just to replace the text input field (<input type="text" name="dependent.relationship.documentation">) with a file upload field (<input type="file" />.

Actually supporting this would probably involve using HTML5's file API, base64ing the file, and stuffing it into a string...but that presents its own challenges. Alternately, see how Alpaca does it.