TLJH is a great base to build 'stacks' on top of
for various use cases. These 'stacks' should be built by
people who are domain experts in their fields, and easily
updateable with new TLJH versions. Extension points need
to be very clearly defined & evolvable, so we can modify
TLJH without fear of breaking everything.
[pluggy](https://pluggy.readthedocs.io/) is the plugin
mechanism for pytest spun out into its own library,
and fits our requirements well.
There is an experimental pangeo stack in progress at
https://github.com/yuvipanda/tljh-pangeo for an example
of how this would work
We do not want users to hand-edit YAML files. This has been a
major source of bugs and confusion for users in z2jh. Doing so
in a terminal text editor makes it even worse.
This lets users type commands directly to modify config.yaml file
rather than edit files directly. This makes it a lot less error
prone and user friendly.
Advanced users can still edit config.yaml manually.
Fixes#38
- Load config only once at startup.
A lot of jupyterhub config (like user lists) take effect only at
startup, so live reload is not super useful. It will make the
software more complex, so let's not do it.
- Add pyyaml as a dependency of tljh.
- Remove escapism dependency since it is not actually used
