Prepare for repo ownership transfer

Release 0.5.2

Bug fixes
- Custom metadata columns are not filtered out
- Fixed Pandas FutureDeprecation warning on frame.append

Release v0.5.0 of PSDS Eval

- Operating point arrays are initialised with np.nan
- Ground Truth and Metadata tables drop extra columns
- Fixed Numpy type deprecation warnings

Release v0.4.0 of PSDS Eval

- input tables with invalid indexes no longer create issues (fix for
  issue #3: PSDSEval.add_operating_point needs index column explicitly
  right now.)
- ground_truth table and detection tables are now checked for invalid
  events (events with onset > offset or with overlapping events from
  the same class). An error is raised if invalid events are found.
- zero length events are now automatically omitted from ground_truth
  and detection tables before the evaluation.
- tests and examples are updated to fix the overlapping labels in DCASE
  ground truth example

Release v0.3.0 of PSDS Eval

- Allow user to insert information per operating point
- Retrieve operating points based on given criteria

Release 0.2.0

Features
========
- Introduced a new plot function for displaying per-class PSD-ROC.
- Added support for external axes to the plot_psd_roc function.
- Added the duration_unit as class attribute. It is then returned by
  the PSDSEval.psds function in the PSDS namedtuple.
- Added a jupyter notebook that shows how the PSDS can be used to
  extract performance insights for the DCASE2020 Task 4 baseline
  system. It also explain in more details few features of PSDS metric.

Release 0.1.0

Features
========
- Added function for computing macro F-score. It is defined as the
average of the
per class F-score metrics.

Bug fixes
=========
- Relaxed check of increasing monotonicity for eTPR (effective True
Positive Rate).
This check is performed in the function that calculates the area under
the PSD-ROC
curve and it is now disabled when the parameter `alpha_ct > 0`. In this
case such
property can't be guaranteed.
- The confusion matrix (`counts`) was built with inverse axis which then
caused
the cross-trigger rate to be assigned to the wrong class.