Tests and doc site can now run without node, using only
"lein figwheel". Tests and site are then re-run automatically
whenever a source file changes.
The doc site is now generated into "outsite/public", and can be
copied into the "gh-pages" branch with "make build-gh-pages".
"make push-gh-pages" builds the doc site and pushes it upstream
to the gh-pages branch there.
Generation of html pages is now handled completely in
ClojureScript, loaded from "bin/gen-site.js".
Link handling is a bit simplified.