Plan project common introduction in documentation

This task originates from QSR-1236:

Plan where to move the common introduction part that is replicated in multiple documents

Definition of Done

• Suitable solution is drafted 
• The common introduction part is aligned with product management
• The common introduction part mentions at least automotive, medical devices and industrial automation as industries that are relevant for the QSR
• The introduction is aligned with https://resources.qt.io/whitepaper/white-paper-functional-safety 
• The document management guidelines page contains reference to it 
• All impacted documents are updated accordingly 
• Possible images are stored in the project SharePoint site