use Kafka instead of RabbitMQ for messages. Both for broadcast
messages (probe controller) and distributed messages (alerting)
big refactor of alerting to simplify things. Removed most
bosun dependencies and all of the bloat associated with it.
As our "alerting" rule is simple and static, just compute it
from the raw graphite results. No need to complicate things by
using Bosun's expression language
use publishing code from raintank-probe for pushing metrics and
events to tsdb-gw. This is mostly to support any legacy probes
that still send metrics/events to worldping-api and not directly
to tsdb-gw
proxy graphite render requests to tsdb-gw. This is to support
legacy worldping-app's that are not using a recent verison.