Doozer srv

Build doozerd uri  throud srv record
Remove unnecessary loop in test
Add the "doozer-backup" in name of the blob @xla 
`doozer.coordinator.prod.bazooka` is SoundCloud specific and should be replaced with a neutral default.

I think all occurrences of `SRVAddress` can safely be shortened to just `SRV` for better readability.

Also the opening comment in the end should be removed.