- QSettings object needs special care, as file was re-created on exit
- Append a cleanup function as soon as possible to ensure temporary dirs & files are removed in any case
- prefer addCleanup() over tearDown(), keeping creation and cleanup together
- get rid of useless ConfigSection.__config
- use name instead of full key (as section name is fixed)
- add support for qt type
- remove _convert_to_bool(), unneeded with qt type support