xml projects groups users

<group name="Readers" description="A group for users who have read access across the project">  
   <permissions>  
     <permission name="GENERIC_READ" class="PROJECT" allow="true" />  
     <permission name="GENERIC_READ" class="CSS_NODE" allow="true" />  
     <permission name="WORK_ITEM_READ" class="CSS_NODE" allow="true" />  
   </permissions>  
</group>