support storing documentation for functions.

js/pixl/public/index.html

        pixl.scripts.stringify = function(name, scriptObj) {
            var script = "window." + name + " = " + "{};\n";
            for (var funName in scriptObj) {
                script += name + "." + funName + " = " + scriptObj[funName].toString() + ";\n";
            for (var fnName in scriptObj) {
                var fn = scriptObj[fnName];
                script += name + "." + fnName + " = " + fn.toString() + ";\n";
                if (fn.doc) {
                    script += name + "." + fnName + ".doc = " + JSON.stringify(fn.doc) + ";\n";
                }
            }
            return script;
        };