desktop-entry-spec: Add an optional Keywords key

[Simon McVittie]

On Fri, 02 Dec 2011 at 12:35:09 +0000, Peter Brett wrote:
> I just checked -- the Trinity DE (forked from KDE3) is still using the
> "Keywords" key (and not "X-KDE-Keywords").  For example:
> 
> http://git.trinitydesktop.org/cgit/tdebase/tree/kcontrol/input/mouse.desktop
> 
> So yes, this might be a showstopper...

... although mouse.desktop does seem to have keywords broadly compatible with
the GNOME proposal (except that they're comma-separated).

KDE and/or Trinity people: is your old Keywords key sufficiently close to the
meaning suggested by GNOME that the spec could just bring back the old KDE
thing and make it official?

    S