Fix typos etc

[jonathan-s]

I had a readthrough of the repo. All in all I think it looks good, you do some clever things.

Some improvements that could possibly be made is to have settings for two things.

• the javascript folder; in case they somehow want to name it differently; not super important as I think javascript is a pretty reasonable name.
• be able to use yarn instead of npm. It's basically a drop-in replacement.

Those will be bundled in a single application.js file which will be copied to static/js/application.js

If I've got several django apps, will it work correctly? I assume that the stimulus command will create several application.js if you do it for several django apps. I haven't tried, but when reading through the code that's what I asked myself.

Have a watch command.