sound capplet patch for visual bell

[Bill Haneman <bill haneman sun com>]

Hi Jonathan;

Got bogged down today.  Plugging away at this however, it's next in the
pipeline (but I hafta go for a couple hours now).

Plan, based on what you and Jody have said in response to Calum's and my
original capplet: make this a new notebook page in sound capplet, called
"system bell".  (Migrate the Keyboard->Sounds featurelet into this
sounds page too; it's overlapping functionality).

this doesn't include the "anti-patch" to take this out of
keyboard->sounds yet, since I think we need to consider how much of the
existing UI to migrate and whether to preserve the existing string gconf
key for "bell_mode".  I don't mind either way, but until we have a clear
answer I think we should use the existing (functional but redundant)
audio-bell key.

best regards,

Bill