This currently assumes the event, that is replied to, is already
fetched. If it isn't, it will render an empty reply. In the future we
should fetch replies before rendering them.

It is a bit of a hack, but it works...

Also lays a bit of groundwork for better reply rendering

I suck at sizing so the images in the message are currently hardcoded to
300 pixels in width...

Text selection over multiple items doesn't work yet