All the new panels have a standard 24px margin now, so
since we're already splitting the info pages into separate
panels, also fix this minor annoyance.
https://bugzilla.gnome.org/show_bug.cgi?id=779216
Increasing width of a column makes column in each row to have the same
width. So it is unnecessary to set 3rd column of each row separately to
have the same width. Let's do it just once.
https://bugzilla.gnome.org/show_bug.cgi?id=779216
Using "OS name" is clearer than "Base system" when we want
to check what's the current OS/distribution combination is.
Fix that by renaming the label.
https://bugzilla.gnome.org/show_bug.cgi?id=770593
Having the OS name and architecture at the same place proved
to be harder to understand than having the processor arch.
Fix that by splitting the OS name and type labels in different
rows.
https://bugzilla.gnome.org/show_bug.cgi?id=770593
