mimetypes & about

[Jason A. Donenfeld]

Hi Christian,

I've merged your series. Thanks a lot for that.

Also, I wound up rewriting the mimetype-from-file function to be a lot
more clear and less error prone:
http://git.zx2c4.com/cgit/tree/shared.c#n564

I also expanded the send-plain list to include video/:
http://git.zx2c4.com/cgit/tree/ui-summary.c#n108

I imagine at some point people will have various requests here, and
we'll wind up being convinced to add an option for this...

Jason