update readme

README.md

 | setTabBadge         |    ✅    |       ✅    | [Contribute](CONTRIBUTING.md)|
 | switchToTab         |    ✅    |      in development    |[Contribute](CONTRIBUTING.md) |
 | toggleNavBar        |   ✅     |      [Contribute](CONTRIBUTING.md)      | [Contribute](CONTRIBUTING.md)|
+| navBarCustomView        |   ✅     |      [Contribute](CONTRIBUTING.md)      | [Contribute](CONTRIBUTING.md)|
+
 
 Element tranisitions, adding buttons and styles are not yet implemented. [Contribute](CONTRIBUTING.md)