fixing ToolTip so that it properly invalidates text properties on font/color change, and signals redraw when layout properties change
fixing ToolTip so that it properly invalidates text properties on font/color change, and signals redraw when layout properties change

ContinuumIO/chaco,ContinuumIO/chaco,ContinuumIO/chaco,tommy-u/chaco,burnpanck/chaco,burnpanck/chaco,burnpanck/chaco,tommy-u/chaco,ContinuumIO/chaco,tommy-u/chaco