do it themselves. (Some of these programs actually depended on this
beyond compiling the definition of struct ifinfo!) Also fix up some
other #include messes while we're at it.
man pages up to mdoc guidelines and fix some minor formatting glitches.
Also fixed a number of man pages to not abuse the .Xr macro to
display functions and path names and a lot of other junk.
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.
