Sync traceroute(8) with head.

Sync traceroute(8) with head.

Merges r215937,216184 and r211062,215880,220968:

- Remove unused traceroute(8) contrib code from head
- make WARNS=3 clean
- fix an operator precedence bug for TCP tracerouting
- Remove unneeded struct timezone passed to gettimeofday().
- Remove clause 3 and 4 from TNF licenses.
- Check return code of setuid() in traceroute.

Requested by:	tuexen

git-svn-id: svn://svn.freebsd.org/base/stable/8@235137 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f