Document adding pages

[mstriemer]

One commit with some documentation, one with the page that I made while writing the documentation. That might be weird that the page already exists so you can't really follow it but we'll probably want something like this so I included it.

[coveralls]

Coverage remained the same at 100.0% when pulling 223397e on mstriemer:document-adding-pages-309 into 79c16e3 on mozilla:master.

[mstriemer]

I noticed that we could abstract the entities reducers like addons and users away entirely. It was really just copy/paste. The best would be to have an entities reducer that nests all of the normlizr entities under entities, so this would impact other parts of the code.

It might be nice to add redux-thunk even though we're using redux-async-connect. I think we'd like to be using thunk instead as it seems more popular, we just need to figure out the server-side rendering bit. Using thunk would allow us to move the loadEntities dispatch into middleware which would clean things up a little.

[muffinresearch]

Good work on starting this now 👍. I know we'd said we wanted some docs but it would have been easy to end-up not getting around to it.

[muffinresearch]

CSS is currently in its own directory as opposed to being like this next to the JS.

[mstriemer]

I've been putting my CSS next to the JS it belongs to. We should pick one way though. Maybe we should make a list of things we haven't been consistent on and go through it and enforce stuff with eslint/tests.

[mstriemer]

Andy suggested putting these on Read the Docs which I think is a good idea. I'll figure out how to get them up there in a bit.