Skype attachments aren't transmitted

[tfreedman]

If someone sends you an attachment, there's zero indication of this on the matrix side of things. This has led to a couple awkward situations where someone has attached something and referred to it without me being able to see what they're talking about (without opening Skype).

Ideally, it would be great if attachments showed up within Matrix, and Matrix attachments were transmitted back to Skype, but a quick fix would be to display something saying that there's an attachment (even if it can't be accessed directly).