Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

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

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

Get rid of several unneeded includes (if.h, if_var.h, if_mib.h).

Add a program for configuration of the ATM drivers and the IP over ATM
stuff. This utility allows inspection of the ATM characteristics,
the PHY layer, including statistics of both, the retrival of the
list of currently open channels and also allows access to utopia(4).