You need to use v1.0.1. Otherwise, the "push" will be grayed out in the plugin. For some reason, when I downloaded the plugin from the Unity Asset Store, I did not get the latest version. I will freely admit that it might be user error on my part because I am still figuring out Unity. Anyway, you can download Github for Unity from here:
https://github.com/github-for-unity/Unity/releases
