As a Qt developer, I want to use qOffsetStringArray() for all my string data needs.

There are some manually-created tables in QtCore that cannot, yet, be ported to qOffsetStringArray(), because that would be a pessimisation.

There are four levels on which this function can be improved:

1. work on more than just char character types
2. detect empty strings and store it as the trailing end of a non-empty string
3. detect duplicate strings and store them only once
4. detect common suffixes and store them overlapping

I will create sub-tasks with individual acceptance criteria.