Added a basic frame for the canvas-drawing plugin.

jquery.flot.canvas.js

+/* Flot plugin for drawing all elements of a plot on the canvas.
+
+Copyright (c) 2007-2012 IOLA and Ole Laursen.
+Licensed under the MIT license.
+
+Flot normally produces certain elements, like axis labels and the legend, using
+HTML elements. This permits greater interactivity and customization, and often
+looks better, due to cross-browser canvas text inconsistencies and limitations.
+
+It can also be desirable to render the plot entirely in canvas, particularly
+if the goal is to save it as an image, or if Flot is being used in a context
+where the HTML DOM does not exist, as is the case within Node.js. This plugin
+switches out Flot's standard drawing operations for canvas-only replacements.
+
+Currently the plugin supports only axis labels, but it will eventually allow
+every element of the plot to be rendered directly to canvas.
+
+The plugin supports these options:
+
+    canvas: boolean,
+    xaxis, yaxis: {
+        font: null or font spec object
+    }
+
+The top-level "canvas" option controls whether  full canvas drawing is enabled,
+making it easy to toggle on and off.
+
+By default the plugin extracts font settings from the same CSS styles that the
+default HTML text implementation uses. If *.tickLabel* has a *font-size* of
+20px, then the canvas text will be drawn at the same size.
+
+One can also use the "font" option to control these properties directly. The
+format of the font spec object is as follows:
+
+    {
+        size: 11,
+        style: "italic",
+        weight: "bold",
+        family: "sans-serif",
+        variant: "small-caps"
+    }
+
+*/
+
+(function($) {
+
+	var options = {
+		canvas: true,
+		xaxis: {
+			font: null
+		},
+		yaxis: {
+			font: null
+		}
+	};
+
+	function init(plot) {
+
+	}
+
+	$.plot.plugins.push({
+		init: init,
+		options: options,
+		name: "canvas",
+		version: "1.0"
+	});
+
+})(jQuery);