Some tweaks to the README

[lorcan]

Work in Progress

• Shortening the table of contents
• Putting the "defining factories" stuff together, and before the "using factories" stuff
• Using relative links for the cross-linking (better experience for forks)
• Moved the changelog to the bottom
• Moved the "how this works" nearer the top
• Small tidy-ups and tweaks to the code snippets
• Misc tweaks to other code.

I feel like this could use more eyes :-)

More context from earlier discussions over at lorcan#1

[danielspaniel]

I will pull this branch and check it out

[danielspaniel]

I think it all looks fine Lorcan. I see no problem with merging this when you feel like you are all set.

[lorcan]

👍 if you're happy, I'm happy

[danielspaniel]

Thanks for making this effort Lorcan. The docs are super important, and it is great that you took the time to make it better.