Some more stuff brought into the 2.8 branch

[Chris Turner]

Matthew Dillon wrote:
    * Added sysctl kern.sysbeep_enable (defaults to 1).  For those people
      like me whos laptops would beep every time a terminal beep occured,
      it can get rather annoying in a conference or public place.  Setting
      this to 0 will disable the annoying beeps.
Just want to point out there's some functionality for this as well with:

kbdcontrol -b visual
and
xset b off