We already blocked x-moz-file(-promise) and x-moz-place* but of course people
would find ways to abuse other internal types. This change now blocks everything
except x-moz-url types which are harmless. (i.e. whitelist instead of blacklist)
Since these are just interpreted comments, there's 0 impact on actual code.
This removes all lines that match /* vim: set(.*)tw=80: */ with S&R -- there are
a few others scattered around which will be removed manually in a second part.
