Support JupyterLab 3.0

[ChrisCarini]

Checklist

Please ensure the following tasks are completed before submitting a feature request.

• [x] Read and understood the Code of Conduct.
• [x] Searched for existing issues and pull requests. -- Similar: #138 - Support JupyterLab 2.1

Description

Description of the feature request.

This feature request proposes adding support for JupyterLab 3.0.

Related Issues

Does this feature request have any related issues?

Related issues #138 (Support JupyterLab 2.1)..

Other

Any other information relevant to this feature request? This may include screenshots, references, sample output, and/or implementation notes.

JupyterLab 3.0 was released on 2021-01-05 -> https://blog.jupyter.org/jupyterlab-3-0-is-out-4f58385e25bb

Error Output

ValueError: The extension "@jupyterlab/dataregistry-extension" does not yet support the current version of JupyterLab.

Conflicting Dependencies:
JupyterLab              Extension        Package
>=3.0.9 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/application
>=3.0.7 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/apputils
>=5.0.5 <5.1.0          >=3.0.0 <4.0.0   @jupyterlab/coreutils
>=3.0.9 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/docmanager
>=3.0.9 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/filebrowser
>=3.0.9 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/notebook
>=3.0.8 <3.1.0          >=1.0.0 <2.0.0   @jupyterlab/rendermime
>=17.0.1 <18.0.0        16.8.4           react

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[gepcel]

Seems that neither data-explorer extension for jupyterlab nor data-explorer for atom works anymore.