Scap/Scap3 check scripts

Scap3 can run check scripts for each phase of deployment.

NRPE checks

nrpe check type for reusing existing Icinga/NRPE checks in deployments.

By default, checks are loaded and registered from all NRPE definitions in /etc/nagios/nrpe.d and can be referenced in checks.yaml using type: nrpe.

checks:
  service_endpoints:
    type: nrpe
    command: check_service_endpoints
    stage: promote