[feature request] Add ability for yurtctl to deploy yurthub in cloud nodes.

[DrmagicE]

What would you like to be added:
Add ability for yurtctl to deploy yurthub in cloud nodes.

Why is this needed:
The working mode feature(which is used to specify where the yurthub is working) has been added to yurthub, but the yurtctl command currently will only deploy yurthub on edge nodes.

Besides deploying yurthub on the cloud-side manually, I think we should also add this feature to improve ease of use.

others
/kind feature

[rambohe-ch]

@DrmagicE It's a good idea to add this feature for yurtctl. Would you like to take over and solve this feature?

[DrmagicE]

@rambohe-ch Sure, I would like to.
/assign @DrmagicE

[DrmagicE]

I would like to add yurtctl convert cloudnodes sub command to yurtctl. This command basically do the same thing as yurtctl convert edgenodes do. The only difference is that yurtctl convert cloudnodes will set --working-mode=cloud to yurthub. What do you think? @rambohe-ch

[rambohe-ch]

I would like to add yurtctl convert cloudnodes sub command to yurtctl. This command basically do the same thing as yurtctl convert edgenodes do. The only difference is that yurtctl convert cloudnodes will set --working-mode=cloud to yurthub. What do you think? @rambohe-ch

@DrmagicE agree +1