* WIP: Adds InfluxDB2 metrics
* Adds basic Prometheus metrics
It's much easier to implement so I'm switching to focusing on it for
now.
* Add some more counters and gauges
Use some labeled counters for backup destinations
* Extract methods for local repo clone and update
It was a little difficult to understand what was going where, esp. with
Go's verbose logging, so I extracted methods where appropriate. This
should also ease some testing concerns down the road.
* Fixes missing y in yaml
* Refactor next run logging
* Add run start and end log messaging
* Adds prom histogram for job duration
* Adds a prom gauge for number of repos discovered
* Switch prom job duration to a summary
I'm really not sure if it should be a summary or a histogram, but
reading about both, it seems like it would be more valuable with
quantiles and not buckets, so summary it is.
* Drop InfluxDB integration for now
We can revert this if we decide to implement InfluxDB after all.
@cooperspencer prefers Prometheus and frankly it's a lot easier to set
up so I'll use it, too, since I already have it running in my
environment anyways!