Short share URLs

[aklinker1]

The current approach of putting the whole conversation in the URL works, but shared links don't look good :/ I'd prefer there be a share a conversation an easier way.

After #13 is implemented, we can use a conversation ID for this. However, I want the shared thread to remain a snapshot of the messages when it was shared, not including any future messages.

[salmin89]

should we use a url-shortener service or hash the url ourselves. Or do we just wait for #13?

[aklinker1]

I say we wait