Disable all collectors with postgres_exporter

[keithf4]

Describe the issue:

The options to disable default postgres_exporter metrics do not work for the collectors. Add the options to disable all of these by default to the example configuration

Tell us about your environment:

• pgMonitor version: 5.1.1
• Container or non-container:
• Container name / image:
• Operating System for non-container:
• PostgreSQL Version:
• Exporter(s) in use (incl. version): postgres_exporter
• Prometheus version:
• AlertManager version:
• Grafana version: