Update Getting Started page

Update Getting started page: http://www.condep.io/docs/4-0/quick-start/

- Replace `Artifact` references in text with corresponding `Runbook`-references
- Update code examples according to new syntax for `Runbooks`
- Add link to http://www.condep.io/docs/4-0/condep-exe/ at the bottom where `condep.exe` is discussed