PyFstat/PyFstat: v1.6.0

This is the v1.6.0 release of PyFstat, a python package for gravitational-wave data analysis with the F-statistic, dated 19/08/2020. This release requires at least python 3.6. From the changelog: Writer classes, including several backwards-incompatbile changes: removed lots of default values where there isn't really a logical "default"; e.g. detectors and signal parameters now always need to be explicitly set. more flexible setup getting info from noiseSFTs (tstart, duration now optional and used as constraints) can now auto-estimate SFT frequency band if not set by user (assuming a single-template search) added manual ephemerides options removed add_noise option, same behaviour can still be controlled through options sqrtSX or noiseSFTs no .cff file generated any more if h0==0 (no signal) verbose option for make_cff() and make_data() methods clearer error messages in many cases ComputeFstat, SemiCoherentSearch and derived classes: fixed internal maxStartTime default if not set by user by that, fixed the SemiCoherentSearch segments auto-setup added Tsft as user option clearer error and logging messages improved helper_functions.get_sft_array() extended, cleaned up and further modularised test suite updated examples to changes in Writer and other classesSee record https://doi.org/10.5281/zenodo.1243930 for previous versions of PyFstat up to v1.4.1