This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Fix things so it *really* won't compile if the environment isn't there.
This commit has been sitting in my to-do list for 2 months. Xditview
should never have been half-removed, so now it's back with a vengance
because we want to keep groff intact as a package.