returns xml fragment.
<response success="true" error="">
if success attribute is "true", the global user groups has been retrieved successfully like xml sample below
if success attribute is "false", the error attribute indicates the encountered error.
The sub nodes return a list of global user groups
<response success="true" error="">
<usergroups>
<usergroup GroupName="Accountants" />
<usergroup GroupName="Auditors" />
<usergroup GroupName="Global Authors" />
<usergroup GroupName="Human Resources Staff" />
<usergroup GroupName="Information Technology Staff" />
<usergroup GroupName="Managers" />
<usergroup GroupName="Sales and Marketing Staff" />
</usergroups>
</response>