Merge branch 'cupy' into 'master'

.gitignore

.gitlab-ci.yml

binder/environment.yml

conftest.py

doc/notebooks/00_tutorial_lbmpy_walberla_overview.ipynb

doc/notebooks/01_tutorial_predefinedScenarios.ipynb

...books/10_tutorial_conservative_allen_cahn_two_phase.ipynb

lbmpy/advanced_streaming/communication.py

lbmpy/max_domain_size_info.py

lbmpy_tests/advanced_streaming/test_fully_periodic_flow.py

...tests/advanced_streaming/test_periodic_pipe_with_force.py

lbmpy_tests/cumulantmethod/test_flow_around_sphere.py

lbmpy_tests/cumulantmethod/test_periodic_pipe_flow.ipynb

...ios/phasefield_allen_cahn/phasefield-capillary-wave.ipynb

...arios/phasefield_allen_cahn/phasefield-gravity-wave.ipynb

lbmpy_tests/full_scenarios/shear_wave/scenario_shear_wave.py

lbmpy_tests/phasefield/test_n_phase_boyer_analytical.ipynb

lbmpy_tests/phasefield/test_n_phase_boyer_noncoupled.ipynb

lbmpy_tests/phasefield/test_numerical_1D_nphase_model.ipynb

lbmpy_tests/test_boundary_handling.py