* chore: switch to yarn
BREAKING CHANGE: Pinafore is now using yarn rather than npm, so those
who self-host will need to stop running e.g. `npm install` and run `yarn
install` instead.
* install latest yarn
* fix: update to latest sapper
fixes#416
* fix error and debug pages
* requestIdleCallback makes column switching feel way nicer than double rAF
* add export feature
* add better csp info
* workaround for sapper sub-page issue
* clarify in readme about exporting
* fix now config
* switch from rIC to triple raf
* style-loader is no longer used
* update theming guide
Nolan Lawson