Fix language tags in doc-snippets

The doc-snippets were inconsistent
(no spaces before title, small-caps, JS
instead of JavaScript, etc.)

apps/tests/ui/progress/progress-tests.ts

@@ -13,12 +13,12 @@ import progressModule = require("ui/progress");
 // ```
 
 // Binding the Progress value property to a view-model property.
-//```XML
+//``` XML
 // <Page loaded="pageLoaded">
 //   {%raw%}<Progress value="{{ someProperty }}" />{%endraw%}
 // </Page>
 //```
-//```JS
+//``` JavaScript
 // function pageLoaded(args) {
 //   var page = args.object;
 //   page.bindingContext = { someProperty : 42 };