VSTU is natively supported and you just need to reinstall VSTU.
EDITORPACKAGE NOT LOADING VISUAL STUDIO TOOLS FOR UNITY INSTALL
To do it manually, download and install the VSTU version that matches the Visual Studio version you have installed and want to use with Unity, as described in the following sections. The easiest way to update is through the update tab of the Visual Studio extension manager. Of course they’re context sensitive, and only appear if you’re actually working in a NetworkBehaviour.
Today, we’re pleased to announce the VSTU 2.2 release that fixes common integration issues that developers are facing. A few months back we released Visual Studio Tools for Unity 2.1 (VSTU), the first release to be natively supported by Unity on Windows, making it much easier for game developers to use the rich capabilities of the Visual Studio IDE while developing Unity games.