Use label instead of alias for displaying tab text in editor dialog

Author: MvdDonk

src/Our.Umbraco.DocTypeGridEditor/Web/UI/App_Plugins/DocTypeGridEditor/Views/doctypegrideditor.dialog.html

@@ -11,7 +11,7 @@
         <div ng-switch-when="edit">
 
             <fieldset ng-repeat="tab in model.node.tabs">
-                <legend style="font-size: 18px;">{{tab.alias}}</legend>
+                <legend style="font-size: 18px;">{{tab.label}}</legend>
 
                 <umb-property property="property"
                               ng-repeat="property in tab.properties">