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**Enhancements**
- Limit calculation for k=0 provided (resulted in nan before)
- Alternative hankel kernel now selectable: sqrt(x) * J(nu, x)
- Caching of series factors for faster calculations
- Various infrastructure upgrades (setuptools_scm, pre-commit, black)
**Bugfixes**
- Saver calculation of xrange_approx
**Deprecations**
- Methods ``G`` and ``deltaG`` now named ``final_term_amplitude`` and ``slope_of_last_term``.