title: How to set a revision number for svn external?
body: <p>So I have this file Mobile.framework and if I do a <code>svn propedit</code> i get</p>
  
  <pre><code>svn propedit svn:externals
  </code></pre>
  
  <p>It brings up </p>
  
  <pre><code>Mobile.embeddedframework  svn+ssh://../Mobile.embeddedframework
  </code></pre>
  
  <p>This is pointed to the head. </p>
  
  <p>I want to edit this and set it to -r1209. Whats the correct way to set it to a revision?</p>