Add support for GitHub as Source provider

[RobReus]

In addition to S3, and the newly added CodeCommit source providers, I would like to see GitHub be added too for those of us using GitHub instead.

You should be able to select "GitHub" in the CodePipelineSource parameter, and then have a choice if you want to "Poll" or if you want a "Webhook" to be created. A parameter for the GitHub token secret should also be added.

[rakshb]

@RobReus Thanks for the request. We will add this to the backlog for a future release.

[kkvinjam]

IHAC looking for integration with GitHub Enterprise repository.

[groverlalit]

Thanks for creating the feature request. We have added this our backlog.