This commit introduces the test case for rehoming one subcloud.
Test Plan:
PASS: Deploy two DC systems, one with one subcloud and the other
one with only the system controllers. Run the test case and verify
that the subcloud is correctly migrated from one DC system to the
other one and then migrated back to its original system controller.
Change-Id: Ibd95d5abeb302a767f42a6177ef1d087442dc304
Signed-off-by: Gustavo Pereira <gustavo.lyrapereira@windriver.com>
8eae43908e