Okdata-cli

* Updated dependencies to fix security vulnerability in urllib3.

* The new permission API based `WebhookClient` from the SDK is now used instead
of the deprecated `SimpleDatasetAuthorizerClient`.

* [Webhook tokens](doc/webhooks.md) are now tied to an operation on a dataset
(read, write), instead of a specific service.

* [Permissions](doc/permissions.md) can now be administered from the CLI.

* Enabled retries for file uploads.

* The minimum required version of `okdata-sdk` is now 0.6.3.

* Fixed `okdata pipelines instances wizard`, where an outdated version of
`PipelineInstance` was assumed.

* Dataset license is now chosen from a preset list instead of free text.