Read metadata when TextMate packages are loaded

The bundled TextMate packages contain valid package metadata
which should be available when displaying in the packages settings
view.

src/app/text-mate-package.coffee

@@ -27,6 +27,8 @@ class TextMatePackage extends Package
     @metadata = {@name}
 
   load: ({sync}={}) ->
+    @metadata = Package.loadMetadata(@path, true)
+
     if sync
       @loadGrammarsSync()
       @loadScopedPropertiesSync()