More adaptions

lbmpy/creationfunctions.py

lbmpy/phasefield/analytical.py

lbmpy/phasefield/cahn_hilliard_lbm.py

lbmpy/phasefield/nphase_nestler.py

lbmpy/phasefield/phasefieldstep.py

lbmpy/phasefield/phasefieldstep_direct.py

lbmpy_tests/centeredcumulant/test_periodic_pipe_flow.ipynb

lbmpy_tests/phasefield/test_entropic_model.ipynb

lbmpy_tests/phasefield/test_n_phase_boyer_noncoupled.ipynb

lbmpy_tests/phasefield/test_n_phase_paper_boyer_lbm.ipynb

lbmpy_tests/phasefield/test_phasefieldstep_direct.ipynb

...y_tests/phasefield/test_phasefieldstep_direct_boyer.ipynb

...hasefield_allen_cahn/test_phase_field_allen_cahn_2d.ipynb

lbmpy_tests/test_sparse_lbm.ipynb