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* `pyfar.dsp`
* added `linear_phase` (PR 176)
* added `minimum_phase` (PR 185)
* added `zero_phase` (PR 175)
* added `time_window` (PR 178)
* added `pad_zeros` (PR 184)
* added `time_shift` (PR 186)
* added `InterpolateSpectrum` (PR 187)
* Unified the `unit` parameter in the pyfar.dsp module to reduce duplicate code. Unit can now only be `samples` or `s` (seconds) but not `ms` or `mus` (milli, micro seconds) (PR 194)
* `pyfar.dsp.filter`
* Add reconstructing fractional octave filter bank (PR 180)
* Bugfix for mis-matching filter slopes in `crossover` filter (PR 174)
* Refactored internal handling of filter functionality for filter classes (PR 190)
* Added functionality to save/read filter objects to/from disk in `pyfar.io.read` and `pyfar.io.write` (PR 192, 182)
* Improved unit tests
* Improved documentation