That option is a native Dreamweaver option. You would need to ask Adobe why it was removed.
Adobe have deprecated the server behaviors panel, so I would guess that has something to do with it, but it would best to ask for an official response.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.