Update README.md

Update README.md

Merge branch 'main' of https://github.com/fhswf/jupyterhub

fix typo

remove optional data mounts from config

add env for mounts

added env for volumes

Merge pull request #60 from fhswf/beegfs-volume

Add BeeGFS volume in JupyterHub

added data folder mount /data:/mnt/nfs_share/docker/jupyterhub/data

update readme