Change in the "Listing mode" documentation

[Pavel Roskin <proski gnu org>]

Hello!

I was trying to make an automated check for the documentation when I found
that we have a line in mc.1 that nroff cannot break.  That's the
description of the long format in the "Listing Mode" section.

Also the descriptions of the keywords all included highlighted commas, 
making it unclear whether commas are required.

I have changed the documentation so that it uses spaces, not commas, in 
the definitions for the listing modes.  The default modes in the source 
have been changed as well.

The keyword "mark" has been moved up, closer to the "type" keyword, since 
it's specific to the file rather than a purely decorative separator.

Help in updating the translations will be appreciated.

-- 
Regards,
Pavel Roskin