Adding context to strings in the shortcut windows

[Piotr Drąg <piotrdrag gmail com>]

Hi,

I really love the shortcut windows that you are introducing this
cycle, but I'm concern about translation. I would like to add a
requirement to the GNOME Goal that every translatable string in
help-overlay.ui must have the attribute context="shortcut window" (or
similar) set. This way we can differentiate the help strings from e.g.
menus and translate them accordingly.

I would be happy to add the context attribute to the already existing
shortcut windows, if you are OK with this change.

Best regards,

-- 
Piotr Drąg
http://raven.fedorapeople.org/