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

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

Add missing newline in last line of file.

Uncovered via: fromcvs vs. svn
Approved by: ed (co-mentor)

Link pf 4.1 to the build:
- move ftp-proxy from libexec to usr.sbin
- add tftp-proxy
- new altq mtag link

Approved by: re (kensmith)