title: Are required plug-ins automatically installed when installing a plug-in that has dependencies?
body: <p>I'm developing a plug-in that relies on CodePro and Sonar plugins. I added these plugins in the "Required Plug-ins" section of the Plug-in Manifest Editor.
  When I try to install my plug-in on a fresh Eclipse instance then I get the error: "Missing requirement: XYZ plugin requires bundle 'ABC' but it could not be found.".
  Is it a requirement that users have to manually install these required plug-ins before installing my plug-in?
  Or is there a way Update Manager can automatically download and install these required plug-ins before mine?
  If there is a way, how can I do that? I've read many, many articles, blogs and forums but did not a clear response on that.
  I'd appreciate any help.</p>