Update this blog's engine from middlemanapp to gatsby

This site has for a long time been generated using the middlemanapp site generator.

I've always found it to be slightly awkward - especially when it's time to update dependencies - since it's ruby based and I don't spend that much time in the ruby world any more.

However - my day job has a lot of react - so I thought it time to finally check out Gatsby.

I'd looked at this before but never really got the feel for it. However - this time - with a good example from this egghead.io course I managed to get it working surprisingly quickly.

Some things I've changed from the normal gatsby/markdown setup - things like generating the path for a page based on its filename rather than a frontmatter path entry.

Status:

• There are some parts still to do: github issues list
• I can't test all the google search/google adsense stuff until its on the correct domain - so they may/may not work right just now
• I'm not too fond of the renaming of files that gatsby-remark-copy-linked-files does for linked files - but not so much that I can't live with it for now