Constness changes

[melted] / demo / entity.westley

<?xml version="1.0"?>
<!DOCTYPE westley SYSTEM "../src/modules/westley/westley.dtd" [
        <!ENTITY name "Westley">
]>
<westley>
  <producer id="producer0">
    <property name="mlt_service">pango</property>
        <property name="text">Hello &name;,
My name is Inigo Montoya.</property>
  </producer>
</westley>