Replaces `startVerifyUpstream` and behaves just like
`blocking.loading.strategy`.
We use the bootstrap resolver for any requests that arrive before the
upstreams are initialized.
Move `startVerifyUpstream` to `upstreams.startVerify` so it's accessible
via `UpstreamGroup` and we don't need to pass `startVerify` to all
resolver constructors that call `NewUpstreamResolver`.
Also has the nice benefit of greatly reducing the usage of `GetConfig`.
To declutter the global top level config options i propose the grouping of ports and logging options as child options of top level options.
New structure:
ports:
dns: 43
http: 4000
https: 4443
tls: 853
log:
level: warn
format: json
privacy: true
timestamp: false
Kwitsch