Goal

This is a preparation for an update of the curriculum. The goal is to have an updated curriculum that is state-of-the-art and training providers can rely on for ~2 years. It is a bugfix release for 2020.1:

We explicitly want to do the following:

• Transfer all Learning Goals into new structure (i.e. replace "können, verstehen, kennen")
• adopt new structure which is defined in https://github.com/isaqb-org/curriculum-flex/wiki
• Update (book) references and outdated content
• Add English translation
• Explicitly state that order of chapters is not predefined #52
• Fix form and typos