Display last received file and time (fixes #292, fixes #801)

milestone--

Open to better suggestions regarding the UI part, or wording.
There is now I think (just vimeo being slow), but for the record, first the date popup pops up (with the bootstrap styling), then a short moment later the full filename as a browser tooltip (because it's truncated, probably). Not sure if that's even fixable when I think about it.