Without this field, U2F just isn't working and the accounts with U2F
set up are shown an OTP prompt.

There seems to be no good reason to change group membership when
exchanging tokens, let's try just passing the old one over.

Using CORS-enabled requests in the background.

Allow loading remote images.

Simplifies the device manager code as we don't have to duplicate the
IP/network matching logic there.

Should make the subdivision between apps (idp, sso) more obvious.

Uses the clientutil.Backend abstraction for the keystore client API.

It left the Prometheus instrumentation in server/http.go, while
it is already provided by the ai3/go-common package.

Panic on short reads and other errors.

Uses 'go generate' to invoke sri.py.

Which would be the GeoLite2-Country.mmdb one.

This enables correct (hopefully) support for IPv6 lookups. Also add
support for the special "onion" zone for Tor Hidden Services.

Classic mistake with strings.Split("").

Otherwise gopkg.in/yaml.v2 won't decode strings to []bytes.

The proxy wraps endpoints (exposed as separate HTTP hosts) with single-sign-on
authentication.