As many option have been added to it, the panel started to look overloaded.
With a little rework, it now displays the same options in a cleaner way.
Took opportunity to include some balloon help for the AppIcon option to try
to be clearer than what the short label allows.
Signed-off-by: Christophe CURIS <christophe.curis@free.fr>
A few internationalized format strings have only one %s in the default
while two strings are being passed. Change those defaults to have two
%s's, which means we also have to update the .po files to match. May as
well throw in the extra %s in the translated version while we're at it.
