Add more extensions, update license, add OCI labels
This MR changes the following:
- Add execution time extension, which shows the execution time after each cell in JupyterLab
- Add the resource usage and system monitor extensions to show CPU and RAM usage in JupyterLab
- Add OCI annotations to the image. Not sure how important this is.
- The license is changed to BSD-3, since docker-stacks also uses BSD-3. The images are both based on docker-stacks images (the gpu image only indirectly).
- Some small improvements (save conda config, matplotlib font cache, fix ownership in home directory)