title: Keep version number in one place in project
body: <p>I have a project which when being set up for release, needs the version number in several places.</p>
  
  <ol>
  <li>In the source code, so I can display the version number to the user when the software is running.</li>
  <li>in the name of the executable, say, <code>myprogr2-1.exe</code></li>
  <li>in the folder name where it is to be installed, say, <code>c:\Program Files\MyProg-2.1\</code></li>
  <li>in the name of the installer, say, <code>MyProgr-2.1-Win32-Setup.exe</code></li>
  </ol>
  
  <p>And so forth...</p>
  
  <p>The challange is to find a way to do this so I can keep the one version number in one place, rather than having to update it in in seveal files (cause I will allways forget one).</p>
  
  <p>Are there anyone out there knowing about cunning ways to do this?</p>