title: Eclipse: How can I install an older plugin version from an update site?
body: <p>I want to determine if downgrading one of my Eclipse plugins to the previous version fixes the problem I have.  I was wondering if there is a general method using the plugin's Eclipse update site that I can use Eclipse's install GUI to install an older version of the plugin.</p>
  
  <p>If it matters, the tool of interest is the Scala-IDE at this update site:
  <a href="http://download.scala-ide.org/releases-28/2.0.0-beta">http://download.scala-ide.org/releases-28/2.0.0-beta</a></p>
  
  <p>What I want is the previous build of the 2.0.0-beta.</p>