Improve documentation

[rossmeredith]

I was interested in using this package but currently it's too frustrating to get started. I can't even follow the tutorial since templates are missing. Furthermore some of the documentation seems off. For example at https://djangochannelsrestframework.readthedocs.io/en/latest/examples/observer_model_instance.html it says to first use the "Retrieve" action and then a "subscription" even though the code for each is exactly the same? Doesn't seem right to me.

[johnthagen]

See also

• chat/layout.html referenced in tutorial is missing #174