This adds a couple of dummy asset files protected by the "noassets"
build tag. The purpose is that it should be possible for, for example,
CI tools and static analysis things to compile and analyze the source
tree without our custom asset generation step. Also makes `go test -tags
noassets ./...` work without building assets first.
- Move to ipinfo.io for geoip, rather than Telize. Telize has been closed
down. ipinfo.io has apparently got decent availability, and allows
1,000 requests per day on the free tier. Since requests are made by the
client, this should be more than enough (and the total across all clients
should still be less than this).
- Fix issue where one nonresponsive relay would cause 'data unavailable'
to be shown for many relays. This was caused by the relay status
promise not being correctly added to the list of things being waited
for before the map was rendered. Any delayed relay status requests
would therefore occur after the map was rendered, which was too late.