Fix also some errors in the status template, and update to Bootstrap
4.3.1 and JQuery 3.4.0.

Also add instrumentation for the load balancer module.

Includes a merge of radiod and redirectord, updates to more modern Go
idioms, adoption of the higher level etcd concurrency primitives, and
a lot of other minor implementation changes.

The refactor is still incomplete: the daemons won't compile and the
code to start the RPC servers is missing.