Integrate with third parties APIs

[calavera]

- Do you want to request a feature or report a bug?

This is a new feature.

- What is the current behavior?

There is no way to add information about third party systems, like GitHub.

- If the current behavior is a bug, please provide the steps to reproduce.

- What is the expected behavior?

People should be able to add third party systems to their status pages to let users know that an outage in a third party service might be causing service disruptions.