KerbalStuff to CKAN converter

This is still rough around the edges, but it seems to be working. It's called with:

`ks2ckan Identifier KSID`

For example:

`ks2ckan DogeCoinFlag 269`

The mod being fetched must have an embedded CKAN fragment for this to work.

As this is not end-user code, it should be find to merge even though bits are rough around the edges.
I've tweaked a number of things in here so that things can be downloaded without a full `CkanModule` instance. That's needed for ks2ckan, because it doesn't have full metadata until *after* it's downloaded the file.