This PR checks all active Action Cable documentation for typos and other
fixes. It aims to make sure that when Rails 5 is released, that the
Action Cable docs are up to snuff with the other documentation included
with Rails.
[ci skip]
* Properly indent code sample in ActionCable::Channel::Streams
* Add a doc comment for #stop_all_streams
* Reformat + add <tt> blocks around code references in ActionCable::Base docs
* Clarify and a little better grammar on ActionCable::RemoteConnections
* Correct indentation and clean up ActionCable::Server::Broadcasting code sample