v1.0.0

Added

- `/ping` endpoint, intended for a lightweight healthcheck
- Configurable client ip source for cases when running behind a reverse proxy. Configurable via the `CLIENT_IP_SOURCE`
  environment variable, see [README.md](README.md#environment-variables)

Changed
- BREAKING: Default behaviour for container_health metric now only reports the health status on containers with the
  following label `docker-prometheus-exporter.metric.container_health.enabled`. Configurable with the
  `CONTAINER_HEALTH_FILTER_LABEL` environment variable, see [README.md](README.md#environment-variables)
- BREAKING: Default listen address changed to `127.0.0.1`
- Migrated from [docker-api](https://github.com/vv9k/docker-api-rs) to `bollard`(https://github.com/fussybeaver/bollard)
- `container_health` metric collection performance enhanced on high container count hosts

Removed
- BREAKING: `DOCKER_HOST` environment variable. Now connects via Unix Socket or Windows Pipe