Correct 1BSD release date.

Correct 1BSD release date.

The Quarter Century of Unix book said that 1BSD was released March 1979.
However, the 1BSD tape image that's on Kirk's historical unix collection has an
earlier date.

It was common practice, at the time, to create a new copy of the tape from the
master system when a new tape was to go out, so several different versions of
1BSD, etc were shipped from Berkerely. The date on the 1BSD tape in the Berkeley
archives on Kirk's DVD is dated in January 16 1979 on the label, and has dates
as late as Jan 29 (there's an UPDATE file that says this includes updates
through this date). Note this date as well.