XML : How to create groups in odoo 8?

I would like to create security group in odoo which comes under USABILITY not under User Roles?

  <record id="group_custom_chats" model="res.groups">          <field name="name">Chatting Options</field>          <field name="category_id" ref="bms.crm_lead_custom"/>          <field name="users" eval="[(4, ref('base.user_root'))]"/>  </record>    

the above code results in like below image.

I want to make it comes under Usabilty/Other. Can anybody help me out.

Thanks