title: Error in Tycho while replacing the product ico files
body: <p>We are using tycho v0.13 and maven 3.0 for building our product.<br/>
  We get the following error/warning when building </p>
  
  <blockquote>
    <p>Error - 7 icon not replaced in C:\Users\AppData\Local\Temp\p2.brandingIron7115583353836584113\launcher.exe using D:\Builds\workspace\plugins\icons\app-icon.ico</p>
  </blockquote>
  
  <p>the ico files are all proper.
  as a result window icons are being replaced by the standard eclipse icons.</p>