Remove old CSS/JS, add client-side service polling code.

This strips the concierge user interface down to an unformatted bare minimum,
and adds a client-side `wait_for_required_services` function that uses the
`/setup/poll` REST interface.
Add inverse logo.
Merge branch 'dev' of https://github.com/browndav/medic-os into concierge-refactor
Merge branch 'dev' of https://github.com/browndav/medic-os into concierge-refactor
Layout work in progress; I'll finish this up tomorrow.
Merge branch 'concierge-refactor' of https://github.com/browndav/medic-os into concierge-refactor
Periodic work-in-progress check in.

User interface design is mostly finished, and the layout is almost acceptably
responsive. Still need to hook the password-setting functionality back up, and
then add a second screen that uses the polling functionality and then provides a
"Finish" button. Probably a couple more hours to go.
Another work-in-progress commit.

Setting the password works again; all that's really left to do is wire up the
service polling code to the user interface, and clean up the navigation/flow so
that all of the buttons do what you'd expect.
Stopping point for today.

All of the functionality works, but there are a couple of edge cases that might
still need some attention (e.g. the "previous step" button). This also still
depends on external resources (i.e. Font Awesome via a CDN, Google Fonts); I'll
get those converted over to local-only tomorrow.
Bypass medic-api beneath /dashboard to avoid 502s and failed updates.

During an update, gardener shuts down and restarts the modules it supervises,
including medic-api. If we're accessing the update interface through medic-api,
we're going to have a bad time.

Toward https://github.com/medic/medic-webapp/issues/625.
Merge branch 'dev' of https://github.com/browndav/medic-os into concierge-refactor
Fix race condition on 'Finish' button, fix retry link.
Merge pull request #31 from browndav/concierge-refactor

Merge newly-refactored concierge
Replace CDN links with local resources.
Temporarily bypass medic-api for some special CouchDB URLs.

Toward https://github.com/medic/medic-webapp/issues/631. We need to
figure out what the underlying issue is in medic-api, but this should
buy us some time until we can do that. I've chosen to skip a few of the
special handlers like /_restart, /_active_tasks, and /_uuids for now.
Merge fix for https://github.com/garden20/gardener/issues/22.
Rewrite / to /medic/_design/medic/_rewrite after fail-over.
Merge branch 'dev' of https://github.com/browndav/medic-os into dev
Concierge: Don't hard-code final URL; use nginx redirect instead.

We now have a proper nginx rewrite from `/` to the Medic Mobile app URL.
Be DRY and use it instead of hard-coding the app URL in a second file.
Add dashboard redirect; tolerate multiple slashes.