is in accordance with the information provided at
ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
Also add $FreeBSD$ to a few files to keep svn happy.
Discussed with: imp, rwatson
of the recent WARNS commits. The idea is:
1) FreeBSD id tags should follow vendor tags.
2) Vendor tags should not be compiled (though copyrights probably should).
3) There should be no blank line between including cdefs and __FBSDIF.