title: Merge properties files with Maven assembly
body: <p>I have a problem with maven assembly plugin.</p>
  
  <p>I have a maven project which use several jars. Each jar contains configuration files.
  With another project, I use maven assembly plugin to assemble all configurations in unique jar.</p>
  
  <p>All work fine but unfortunately, two files are the same name and the second overwrites the first.</p>
  
  <p>I don't achieve to tell maven to merge the two files instead of overwrite.</p>
  
  <p>Someone knows how to do that ?</p>
  
  <p>Thanks.</p>