Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Remove leaf node WARNS?=2 (that mainly I added). This should
help the GCC3 transition and CURRENT in general.

Warns cleanups.

MAN[1-9] -> MAN.

Add renice's correct man page to the Makefile.
Submitted by: jkh

This commit was generated by cvs2svn to compensate for changes in r1590,
which included commits to RCS files with non-trunk default branches.

BSD 4.4 Lite Usr.bin Sources