Emphasize on apply rules in example config.

- move all templates into templates.conf
- move service apply ping{4,6} to services.conf
- apply notifications based on vars.sla == "24x7"
- apply scheduled downtime based on host/service name
- apply ping{4,6} based on hostgroup membership
- keep hosts/localhost for real local configuration

Fixes #6266
Documentation: Fix Getting Started based on revamped example configuration.

Refs #6266
Fix null ptr exception in Zone::GetLocalZone()

Fixes #6273
Fix wrong service apply rule examples for ping{4,6}.

Refs #6266
Move more log messages to 'notice' severity.

Refs #6070