Enhance text widget to optionally use "text" attribute

This lets us use the text widget to render text in macros that we don’t
want to be wikified.

core/modules/widgets/text.js

@@ -28,8 +28,10 @@ Render this widget into the DOM
 */
 TextNodeWidget.prototype.render = function(parent,nextSibling) {
 	this.parentDomNode = parent;
+	this.computeAttributes();
 	this.execute();
-	var textNode = this.document.createTextNode(this.parseTreeNode.text);
+	var text = this.getAttribute("text",this.parseTreeNode.text),
+		textNode = this.document.createTextNode(text);
 	parent.insertBefore(textNode,nextSibling);
 	this.domNodes.push(textNode);
 };

editions/tw5.com/tiddlers/widgets/TextWidget.tid

@@ -0,0 +1,15 @@
+created: 201401191419
+modified: 201401190837
+tags: widget
+title: TextWidget
+
+! Introduction
+
+The text widget displays plain text.
+
+! Content and Attributes
+
+The content of the `<$text>` widget is not used.
+
+|!Attribute |!Description |
+|text |The text to display |