Category for Kernel Gateway

A kernel gateway category would be fine with me. Let’s see if someone else has an opinion on this. Otherwise I’ll create it.

We also seem to have settled on having Q&A as a general point of arrival/landing page (discussion in Direct questions about jupyter/docker-stacks to Discourse?). I like the idea of assuming that most people will post there first and then things get moved as it becomes clearer where they belong.