Added setstyle widget and use it to colour the tag buttons

core/modules/widgets/setstyle.js

@@ -0,0 +1,40 @@
+/*\
+title: $:/core/modules/widget/setstyle.js
+type: application/javascript
+module-type: widget
+
+Implements the setstyle widget.
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+var SetStyleWidget = function(renderer) {
+	// Save state
+	this.renderer = renderer;
+	// Generate child nodes
+	this.generate();
+};
+
+SetStyleWidget.prototype.generate = function() {
+	// Get the parameters from the attributes
+	this.name = this.renderer.getAttribute("name");
+	this.value = this.renderer.getAttribute("value");
+	this["class"] = this.renderer.getAttribute("class");
+	// Set up the element
+	this.tag = this.renderer.parseTreeNode.isBlock ? "div" : "span";
+	this.attributes = {
+		style: this.name + ":" + this.value
+	};
+	if(this["class"]) {
+		this.attributes["class"] = this["class"];
+	}
+	this.children = this.renderer.renderTree.createRenderers(this.renderer.renderContext,this.renderer.parseTreeNode.children);
+};
+
+exports.setstyle = SetStyleWidget;
+
+})();