7ec0eeca56
by the MediaPanel as sprites that interact in some standard way with the mouse. Modified existing ButtonSprite to work this new way, and it now implements CommandSprite, ArmingSprite, and DisableableSprite. One method name changed. git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@3362 542714f4-19e9-0310-aa3c-eee0fc999fb1