- IFS support for several additional pipeline modules (see [overview](https://pynpoint.readthedocs.io/en/latest/overview.html)), including `PcaPsfSubtractionModule`.
- The `processing_type` parameter in `PcaPsfSubtractionModule` is used to select the spectral and/or angular differential imaging processing type.
- Improved use of the `offset` parameter in `SimplexMinimizationModule` and `SystematicErrorModule`.
- Compatibility with Python 3.8, in addition to Python 3.6 and 3.7.
- Creation of `util.apply_func` for multiprocessing functions that need to be pickable.
- Simplifications in `DitheringBackgroundModule` with several deprecated parameters.
- Updated documentation, docstrings and dependencies.