[RCD] Poll: Inline attachments on attachments list

There's a question according to http://trac.roundcube.net/ticket/1488783.

There are messages with related images. Normally, they are referenced in HTML bodies (parts), but not always. So, the question is: should we list such attachments on attachments list. We have a few possibilities:

1. Do not list any in text and html mode (current situation).
2. List only unreferred in text and html mode.
3. In text mode list all, in HTML mode list unreferred only

(Thunderbird's way). 4. List all in text and html mode (only for completenes, I suppose we shouldn't ever choose this option).

Implementing this as a user preference will be overcomplicated, we don't want to make it optional, we should choose one. So, what's your opinion?

For now I have no strong opinion, but I'm somewhere between 1. and 2.