More canonical property order in mw.TemplateData.Model class

This does not have any effect on how this code behaves. It's
only relevant when a human reads the code. I tried to bring the
properties in an order that makes the most sense, grouping stuff
that clearly belongs together, as well as following how stuff is
ordered on
https://www.mediawiki.org/wiki/Extension:TemplateData

Change-Id: Ibbe1027023f8d87bbd0a70411882a25671918670

modules/ext.templateDataGenerator.data/Model.js

@@ -11,17 +11,21 @@ mw.TemplateData.Model = function mwTemplateDataModel() {
 	OO.EventEmitter.call( this );
 
 	// Properties
-	this.params = {};
 	this.description = {};
-	this.originalMaps = undefined;
+
 	this.maps = undefined;
-	this.paramOrder = [];
-	this.format = null;
-	this.paramOrderChanged = false;
-	this.paramIdentifierCounter = 0;
-	this.originalTemplateDataObject = null;
-	this.sourceCodeParameters = [];
 	this.mapsChanged = false;
+	this.originalMaps = undefined;
+
+	this.format = null;
+
+	this.params = {};
+	this.paramIdentifierCounter = 0;
+	this.sourceCodeParameters = [];
+	this.paramOrder = [];
+	this.paramOrderChanged = false;
+
+	this.originalTemplateDataObject = null;
 };
 
 /* Inheritance */