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.
specified in the top level Makefiles.
Previously I missed dozens of Makefiles that skip the install after
using `cmp -s' to decide that the install isn't necessary.