Jupyter-resource-usage

- Autoformatting and documentation [33](https://github.com/jupyter-server/jupyter-resource-usage/pull/33)
- Add section about CPU usage to the README [30](https://github.com/jupyter-server/jupyter-resource-usage/pull/30)
- Make psutil optional dependency of NBResuse [25](https://github.com/jupyter-server/jupyter-resource-usage/pull/25)
- Report the memory usage metrics as prometheus metrics [22](https://github.com/jupyter-server/jupyter-resource-usage/pull/22)

**Note**: this release removed the `/metrics` endpoint that was returning a JSON response. As a result, JupyterLab does not display the memory usage indicator in the status bar with `nbresuse==0.3.4`.

- Made memory limit possibly dynamic via passing a callable in the config. [23](https://github.com/jupyter-server/jupyter-resource-usage/pull/23)
- Track CPU usage [21](https://github.com/jupyter-server/jupyter-resource-usage/pull/21)

- Require authentication for /metrics API Handler [18](https://github.com/jupyter-server/jupyter-resource-usage/pull/18)

- Don't poll in background, since user does not see it [15](https://github.com/jupyter-server/jupyter-resource-usage/pull/15)
- Poll instantly once page is foregrounded [15](https://github.com/jupyter-server/jupyter-resource-usage/pull/15)

This should reduce the number of /metrics requests massively, with minimal interruption to user experience.

- Automatically install & enable extensions [9](https://github.com/jupyter-server/jupyter-resource-usage/pull/9)
- Put nbextension / serverextension enables in different places
- Put nbresuse js files in appropriate path

- Change 'Mem' prefix in display to less cryptic 'Memory'
- Fix primary screenshot to show memory limit too
- Distribute static files via package_data [1](https://github.com/jupyter-server/jupyter-resource-usage/pull/1)
- Add screenshot for memory usage warning
- Configurable memory usage warnings
- More configurability via traitlets
- Consolidate code into single file
- Document memory limit behavior
- Add CONTRIBUTING.md doc
- Updated README