Added waitingSink() to async.js.  Sink decorator which sets wait cursor when busy.
Added waitingSink() to async.js.  Sink decorator which sets wait cursor when busy.

jlhughes/foam,foam-framework/foam,shepheb/foam,foam-framework/foam,osric-the-knight/foam,mdittmer/foam,jacksonic/foam,jlhughes/foam,osric-the-knight/foam,mdittmer/foam,jacksonic/foam,osric-the-knight/foam,mdittmer/foam,foam-framework/foam,jacksonic/foam,foam-framework/foam,mdittmer/foam,jlhughes/foam,jacksonic/foam,foam-framework/foam,osric-the-knight/foam,jlhughes/foam,shepheb/foam,shepheb/foam