update-attachment

[bjohas]

Implements processes described here. https://www.zotero.org/support/dev/web_api/v3/file_upload

Needs more thinking

[a1diablo]

@bjohas Are we taking this next? Is a mapping of verbs to command options have been thought of for this feature?

[bjohas]

I think this depends on #95 - so let's park it for now?

[a1diablo]

Yeah, we can come back to it later.