excise Rickshaw.Graph.Unstacker and allow for consumers to pre-stack …

…if they like; fixes #333

Makefile

@@ -47,7 +47,6 @@ JS_FILES=\
 	src/js/Rickshaw.Graph.Renderer.LinePlot.js\
 	src/js/Rickshaw.Graph.Smoother.js\
 	src/js/Rickshaw.Graph.Socketio.js\
-	src/js/Rickshaw.Graph.Unstacker.js\
 	src/js/Rickshaw.Series.js\
 	src/js/Rickshaw.Series.FixedDuration.js\
 

src/js/Rickshaw.Graph.Renderer.js

@@ -5,7 +5,6 @@ Rickshaw.Graph.Renderer = Rickshaw.Class.create( {
 	initialize: function(args) {
 		this.graph = args.graph;
 		this.tension = args.tension || this.tension;
-		this.graph.unstacker = this.graph.unstacker || new Rickshaw.Graph.Unstacker( { graph: this.graph } );
 		this.configure(args);
 	},
 

src/js/Rickshaw.Graph.js

@@ -173,11 +173,18 @@ Rickshaw.Graph = function(args) {
 
 		stackedData = stackedData || data;
 
+		if (this.renderer.unstack) {
+			stackedData.forEach( function(seriesData) {
+				seriesData.forEach( function(d) {
+					d.y0 = d.y0 === undefined ? 0 : d.y0;
+				} );
+			} );
+		}
+
 		this.stackData.hooks.after.forEach( function(entry) {
 			stackedData = entry.f.apply(self, [data]);
 		} );
 
-
 		var i = 0;
 		this.series.forEach( function(series) {
 			if (series.disabled) return;