Keep configuration and data in distinct directories This allows having distinct volumes for configuration and data (artifact database, generated mapfiles and shapefiles, etc.). While at it, cleanup MapServer configuration a little bit.

<?xml version="1.0" encoding="UTF-8" ?>
<rest-server>
    <!--  The port which the ArtifactDatabase (ArtifactServer) will bind to. -->
    <port>8181</port>
    <listen>0.0.0.0</listen>
</rest-server>