Service tracking issue for GSP-86: Add CreateLink Operation

[joey]

• Rendered GSP
• Tracking Issue

This is the service tracking issue that generated by go-community, please close with comments if not applicable to this project.

Steps

If this service has native support for Link or Symlink:

• Implement CreateLink API
• Add support for List/Stat
• Setup linker tests

If this service doesn't have native support for Link or Symlink, it's optinal to implement the virtual_link features:

• Start a RFC to describe the way to implement the virtual_link feature (take this issue as the tracking issue)
• Implement the RFC
• Setup linker tests

[JinnyYi]

Included in #874.