- maintenance release

 - ci: skip tests that fail on GitHub Actions (Linux/macOS)

- maintenance release

 - ref: cleanup

 - fix: handle more special cases when computing weights for

   projections (#7)
 - ref: make `util` submodule available upon import

 - build: setup.py test is deprecated

 - build: moved from travisCI to GitHub Actions
 - docs: refurbish docs
 - tests: allow 2D Fourier mapping test to fail on macOS
   and Windows (don't know why it fails, probably unstable)
 - ref: replace np.complex256 with np.complex128 in
   _alg_int.py:integrate which does not break any tests but
   works on Windows which sometimes has not support for longdouble
 - ref: replace np.bool with bool due to numpy deprecation warnings

 - ref: move sinogram generation in tests to separate file, thanks @S…

…Zanko

 - ref: deprecation warning int for numpy 1.20.0, thanks @SZanko
 - ref: mor type hints, thanks @SZanko

 - added PEP 484 type hints, thanks @SZanko (#3)

 - maintenance release

setup: bump scipy to 1.4.0 (updated QHull in griddata)