Add document on Deploy Velero in Supervisor Cluster with Images from Private Registry

[lipingxue]

Signed-off-by: Liping Xue lipingx@vmware.com

What this PR does / why we need it: Add a new document about how to Deploy Velero in Supervisor Cluster with Images from Private Registry Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[svcbot-qecnsdp]

Sorry, some of the pre-check tests are failing for this PR !

Please check the Jenkins job for more details https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/827/

[svcbot-qecnsdp]

Congratulations !!

All the pre-check tests passed https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/828/

[lipingxue]

@xing-yang Could you help to review this MR?

[svcbot-qecnsdp]

Congratulations !!

All the pre-check tests passed https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/831/

[svcbot-qecnsdp]

Congratulations !!

All the pre-check tests passed https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/832/

[lipingxue]

@xing-yang I have addressed your comment, please take a look. Thanks!

[svcbot-qecnsdp]

Sorry, some of the pre-check tests are failing for this PR !

Please check the Jenkins job for more details https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/833/

[svcbot-qecnsdp]

Sorry, some of the pre-check tests are failing for this PR !

Please check the Jenkins job for more details https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/834/

[svcbot-qecnsdp]

Sorry, some of the pre-check tests are failing for this PR !

Please check the Jenkins job for more details https://container-dp.svc.eng.vmware.com/job/CNSDP-CI/835/