Track deployments/releases in InfluxDB

Grafana has the ability to plot annotations on a graph based on an InfluxDB query. This allows us to track and plot deployments (for example). An example of this can be found at http://yorick-influxdb.gitlap.com/dashboard/db/transaction-overview:

Tracking this would be as simple as sending the following to InfuxDB via UDP:

deploys version=VERSION TIMESTAMP

Here VERSION would be the version (e.g. "8.5.0") and TIMESTAMP would be the deployment timestamp (UTC) in nanoseconds( Time.utc(...).to_i * 1_000_000_000 in Ruby).

@marin @jnijhof: is this something we can hook into our existing deployment setup? Ideally the timestamp would be the time of when the Unicorn workers are being reloaded opposed to e.g. the package download time.