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

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

Spelling fixes for usr.sbin/

s/adress/address/

Inspired by: OpenBSD
MFC After: 1 week

This commit was generated by cvs2svn to compensate for changes in r6751,
which included commits to RCS files with non-trunk default branches.

Obtained from: The Xkernel source distribution

I hope I'm doing this right.

This is an initial version of bootparamd for FreeBSD based on a public
domain rpc.bootparamd implementation by a gentleman named Klas Heggemann.
This program has apparently been around for a while. The README explicitly
lists the code as public domain, so I guess it's safe to use.

This program is needed for booting diskless SunOS and Solaris machines.
rarpd is also required, but that's in the works too.

I have made two changes to this code:

- Implemented NIS lookups. If /etc/bootparams contains a '+' then the
bootparams map is consulted.

- Allow 0.0.0.0 as a user-specified router address. The SunOS rpc.bootparamd
returns this value in many cases.