Aravinda VK

I will take this up for "GCS-Sprint2"

It is already available in Gd2 API, If `ProvisionerType=loop` specified during add device then it expects directory instead of raw device. We need to change this in gcs deployment where...

Not applicable in GCS setup, both client and peer addresses are same in gcs setup

For uniformity you can retain "Volume name" even in single volume output. Or follow convention similar to volume status ``` volume: TABLE volume: TABLE ```

Issue #1385 talks about showing cluster options. But this PR only includes showing options of all volumes. Cluster options are available in https://github.com/gluster/glusterd2/blob/master/glusterd2/commands/options/commands.go#L25 and the list of valid options are...

@rishubhjain please address the comments and rebase

> @rishubhjain I would suggest disabling the device first so it won't be considered for any volume/brick creation, later we can delete the device. just a question, how are we...

rebase required

- Snapshot related code is not refactored in this PR, I will add Snapshot related changes in separate PR. - This PR also includes device API refactor Please review

Removing GCS tracking label from pull request