E-mail template for asset deliverables

[jenbennings]

We'll need to consider how the packaged (.zip) assets are delivered to the recipient. Whilst we can get away with not having a backend UI on the initial release, if we want this to be an operational tool for us, we'll need to consider this as a design task. It won't need to be perfect, but if we can have some control over the view/template engine, that's a good start.