class Github::Repos::PubSubHubbub

:secret => '...'
:verify => 'sync',
'github://Email?address=peter-murach@gmail.com',
'https://github.com/:user/:repo/events/push',
github.repos.pubsubhubbub.unsubscribe
github = Github.new :oauth_token => '...'
= Examples

* callback - Required string - The URI to unsubscribe the topic from.
* topic - Required string - The URI of the GitHub repository to unsubscribe from. The path must be in the format of /:user/:repo/events/:event.
= Parameters

Unsubscribe from existing topic/event through pubsubhubbub

def unsubscribe(topic, callback, params={})
  assert_presence_of topic, callback
  normalize! params
  _merge_action!("unsubscribe", topic, callback, params)
  post_request("/hub", params)
end