Diefpy

**Fixes**
- fix order of tests for execution time plot by sorting them alphanumerically

**Additions**
- Python 3.11 support

**Removals**
- Python 3.6 support

**Fixes**
- fix issue with files containing a single data point (numpy >= 1.23.0)

**Misc**
- removed duplicated license file
- metadata for Zenodo
- automatic rebuild of documentation on release

**Additions**
- Python 3.10 support
- switch for computing the AUC until the end of the time frame (dieft)
- default colors for plots

**Fixes**
- fix issue in radar charts for approaches generating incomplete results

**Misc**
- iPython notebook showing an example use of the library
- improved documentation: [gh-pages](https://sdm-tib.github.io/diefpy/)
- returning an object of class matplotlib.figure.Figure instead of the matplotlib.pyplot module

- fix issue causing the same values in performance_of_approaches_with_dieft() when the metrics contained multiple tests and approaches

* normalize to 1 instead of overall maximum; leads to the same number of grid lines for all radar charts
* fix issue with radar chart grid lines in matplotlib > 3.2.2 being circular instead of a polygon