Herro! The latest updated official docs are on the Cloud9 support website
Here you'll find details on installing deployment tools from third party vendors to be used in Cloud9 IDE. Besides using terminal tools, there is also a GUI available for Heroku and Azure Sites on all plans. Of course git based deploys will also work without command line tooling.
All commands need to be executed in the terminal (ALT+T) unless stated otherwise.
If you have additions, please note them in the comments and I'll add them to this gist