children of #359: just the URL scheme, only knows html
removing locals usage to perform exporter transform
using initialize instead of slash_exp etc.
fixing typo, prefix path
fixing local file handlers, tests finish
renaming exporters to formats throughout
catching a few missing exp_prefix
allowing for direct specification of exporter
Update faq.md

Add specifics for how long notebooks are cached and how to force an update (see #295)
Merge pull request #376 from nicktimko/master

Update FAQ about time-to-update and how to force an update
Merge pull request #374 from bollwyvl/format-urls

Add /format/ URL handler