Audit chgrp(1)

1) Refactor manpage so it's actually fun to read.
2) BUGFIX: Call (l)chown properly when the H-flag is specified
   (only when depth > 0).
3) BUGFIX: Call (l)chown properly when the h-flag is specified
   (only when depth = 0).
4) BUGFIX: Only recurse() in chgrp() when the initial chownf()
   succeeds.
5) Style fixes, argv-basing.
6) Rename status to ret for consistency.
7) Add blank line before return.

README

@@ -12,7 +12,7 @@ The following tools are implemented ('*' == finished, '#' == UTF-8 support,
 =*| basename        yes                          none
 =*| cal             yes                          none
 =*| cat             yes                          none
-=*  chgrp           yes                          none
+=*| chgrp           yes                          none
 =*| chmod           yes                          none
 =*  chown           yes                          none
 =*| chroot          non-posix                    none