Create a user guide for dpctl queue management and add it to our documentation site.

[diptorupd]

Along with examples, we need to define the spec of dpctl's queue manager. The spec is complementary to API documentation on our GH-pages.

[PokhodenkoSA]

@diptorupd What is the status of this issue? Queue manager is updated now.

[diptorupd]

Still in progress. I will get to it after the release.

[oleksandr-pavlyk]

@diptorupd I suppose we should close this as the feature queue manager is deprecated.

[diptorupd]

@oleksandr-pavlyk sure.