Moving telnet/telnetd from base to pkgsrc

[coypu%sdf.org@localhost]

Hi,

telnet:
1. terrible code, with many abstraction violations
2. something people expect to talk to their legacy machines, which
nobody but them has access to.
3. common use case is served by netcat, already in base.
4. too much superfluous functionality.

Let's pull it out as a package, the alternative being breaking
functionality for the four remaining users.

send hate mail my way.