[Evolution] Bug#652870: evolution 3.8 CalDav requires gnome-keyring

[Justus-dev at piater.name]

Dear Maintainers,

In evolution 3.8 (current testing), CalDav calendars do not work at all
without gnome-keyring; no password prompt is shown, and connection
attempts hang and eventually time out, without a useful error message.
The HTTP error message sent by the CalDav server is 401 Unauthorized.

In evolution 3.4.4 (wheezy), CalDav calendars worked fine without
gnome-keyring.

I'm not sure gnome-keyring should be a hard dependency because evolution
is useful without gnome-keyring (or CalDav calendars), but gnome-keyring
should at least be Suggested or Recommended to guide users towards a
solution.

More to the point, Upstream should take care that evolution output
useful diagnostics and recommendations.

Oh, and I'm not sure installing gnome-keyring is really the only way to
solve this CalDav authentication problem; maybe there are alternative
solutions.

Thanks,
Justus