Allow windows users to download Atom via the release notes view

![release notes - _users_corey_github_release-notes](https://cloud.githubusercontent.com/assets/596/3513392/43a750c0-06c2-11e4-8f44-4d7f91f87a07.jpg)

I think the squirrel icon is small, easily misunderstood and doesn't look clickable, so I would like to have some attention drawn to it. What if we limit the number of times it shows? Having the tooltip stop auto-showing after 3 views should be enough to get the message of the squirrel icon across without being too annoying.