Simplify the setup of bundled assets (#436)

1. Move the generated file to handlers - it better belongs there
2. Ensure that all file serves are also handled by the asset store

Co-authored-by: Marcos Lilljedahl <marcosnils@gmail.com>

config/config.go

@@ -10,10 +10,6 @@ import (
 	"golang.org/x/oauth2"
 )
 
-//go:generate go run github.com/jteeuwen/go-bindata/go-bindata -pkg config -o gen_bindata.go -prefix ../www/ ../www ../www/default ../www/assets ../www/assets/xterm ../www/assets/xterm/addons ../www/assets/xterm/addons/webLinks ../www/assets/xterm/addons/terminado ../www/assets/xterm/addons/fullscreen ../www/assets/xterm/addons/fit ../www/assets/xterm/addons/attach ../www/assets/xterm/addons/zmodem ../www/assets/xterm/addons/search ../www/k8s
-//go:generate go run github.com/play-with-docker/play-with-docker/internal/addgenheader gen_bindata.go "Code generated by go-bindata."
-//go:generate gofmt -w -s gen_bindata.go
-
 const (
 	PWDHostnameRegex      = "[0-9]{1,3}-[0-9]{1,3}-[0-9]{1,3}-[0-9]{1,3}"
 	PortRegex             = "[0-9]{1,5}"