New install_repository_nfsiso_variation
This is covering the NFSISO_variation test as per:
https://fedoraproject.org/wiki/QA:Testcase_install_repository_NFSISO_variation
Change support_server to use support_5 disk image in templates
supposed to be previously created by updated createhdds tool
required for new test.
Signed-off-by: Guy Menanteau <menantea@linux.vnet.ibm.com>