set minimum python version to 3.5

See merge request !28

CI: add --diff to black

See merge request !27

ComputeFstat: extra flag computeAtoms independent of transientWindowType

See merge request !26

ephemerides handling fixes

See merge request !25

 -make clearer when and why we test the .cff file
 -also improve logging output in this function
  and in check_if_cff_file_needs_rewritting()
 -test_makefakedata_usecached: add a call to make_cff()
  in 2nd run as an extra check

 -this used to require exact string match, but SFT header
  can for some reason have the CLAs reordered
  (e.g. when ephemerides are involved)
 -introduce new helper function match_commandlines()
  and do proper unordered set comparison
 -also comment out log info about cff content checking,
  which wasn't actually implemented!

 -add missing self.set_ephemeris_files() call to GlitchWriter.__init__()
 -also write out to CLA in FrequencyModulatedArtifactWriter.run_makefakedata_v4()
 -use getattr for safety

 -consistent with current defaults in lalapps

Fix py3 setup

See merge request !23

 -it's a bit field, so need += in atoms case

fix black style

 -make lalsuite-from-pip the default recommendation
 -don't call any packages that are included in the requirements "optional"

 -drop where="pyfstat" from find_packages()
 -fix license file path
 -add descriptions
 -remove pycuda from requirements.txt
 -add lalsuite to both install_requires and requirements.txt
 -refs #17

Gitlab ci runner setup

See merge request !22

- only black for now

- run against pip-installed lalsuite
- use python3 venv

- logged commandline can contain full path to exectable, so
  cmdline-comparison must be agnostic to that
- fixes failing test against pip-installed lalsuite

Make tests more robust

See merge request !21

- fix test that can otherwise fail (observed on MacOSX)

- any import failure should just be treated as such: we can't import
  that module for whatever reason

Use black pep8 codestyle

See merge request !20

Port to python3 and new lalsuite

See merge request !19

- supply consistent flake8 settings in setup.cfg

- adapt to change in lalsuite API (PulsarAmplitudeParams) in aff93c45

- tests currently fail

add pycuda as optional dependency

See merge request GregAshton/PyFstat!17