had extra <testsuites> element for sample codes

[larrycai]

I run the sample code according to the README, and got the output like

$ ./xunit_report.py
<?xml version="1.0" ?>
<testsuites>
        <testsuite errors="0" failures="0" name="my test suite" tests="1">
                <testcase classname="some.class.name" name="Test1" time="123.345000">
                        <system-out>I am stdout!</system-out>
                        <system-err>I am stderr!</system-err>
                </testcase>
        </testsuite>
</testsuites>

Is it the new feature or I can disable the root element testsuites ?