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

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

This commit was generated by cvs2svn to compensate for changes in r29088,
which included commits to RCS files with non-trunk default branches.

Initial import of BSD telnet. This will be used to build the kerberised
telnet, and after userland diffs have been merged in, will be used to
build the non-kerberised sources as well. (See unifdef(1) for details)