ftests: Add a test for the python bindings to cgroup_cgxget()

ftests: Add a test for the python bindings to cgroup_cgxget()

Add a functional test that exercises the cgroup_cgxget() python
bindings.

-----------------------------------------------------------------
Test Results:
        Run Date:                          Oct 11 22:11:48
        Passed:                                  1 test(s)
        Skipped:                                 0 test(s)
        Failed:                                  0 test(s)
-----------------------------------------------------------------
Timing Results:
        Test                                    Time (sec)
        ---------------------------------------------------------
        setup                                         0.00
        038-pybindings-cgxget.py                      0.04
        teardown                                      0.00
        ---------------------------------------------------------
        Total Run Time                                0.04

Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>