fixes one of the sub-tasks in #1130.
I also went ahead and removed the reply feature, because I cannot get it to work in Android 6.0.1 and I can't find any documentation for it in W3C/WHATWG, so I'm not sure how it is supposed to work.
* 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