Support running Prometheus exporters over SSL
Support running the following Prometheus exporters over SSL
- node-exporter - https://github.com/prometheus/exporter-toolkit/blob/master/docs/web-configuration.md
- postgres-exporter - https://github.com/prometheus/exporter-toolkit/blob/master/docs/web-configuration.md
- redis-exporter - https://github.com/oliver006/redis_exporter
pgbouncer-exporter doesn't seem to be supporting TLS at the moment, I've opened an issue for it - https://github.com/prometheus-community/pgbouncer_exporter/issues/82