examples/org.eclipse.emf.examples.library/plugin.xml

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.0"?>

<plugin>
  <extension point="org.eclipse.emf.ecore.generated_package">
    <package 
       uri = "http:///org/eclipse/emf/examples/library/extlibrary.ecore/1.0.0" 
       class = "org.eclipse.emf.examples.extlibrary.EXTLibraryPackage"
       genModel = "model/extlibrary.genmodel" /> 
  </extension>

  <extension
    point="org.eclipse.core.runtime.contentTypes">
    <content-type
      base-type="org.eclipse.core.runtime.xml"
      default-charset="UTF-8"
      file-extensions="extlibrary"
      id="extendedLibrary"
      name="%extendedLibrary"
      priority="high"/>
  </extension>
</plugin>