The ctrl configuration already existed, just the corresponding column
configuration was missing.
It is now possible to hide and unhide the records within TYPO3 as usual.
Relates: #10230
- Removed individual converters for TYPO3.
Conversion is now handled in a single converter.
- The new converter will import necessary dependencies upfront, e.g.
town or organisation.
- Move import state into extra class.
Relates: #34
