Merge branch 'IncompressibleCumulants' into 'master'

Fix minor issues and remove depricated usage of cumulant LB method

See merge request !70
8 jobs for release/0.3.2 in 16 minutes and 18 seconds (queued for 3 seconds)
Name Stage Failure
minimal-windows Test
c:\users\build\miniconda3\envs\pystencils\lib\site-packages\pyximport\ DeprecationWarning: the imp module is deprecated in favour of importlib; see the module's documentation for alternative uses
import imp

-- Docs:
================= xdist: maximum crashed workers reached: 16 ==================
================== 1 warning in 535994.33s (6 days, 4:53:14) ==================
Cleaning up file based variables
ERROR: Job failed: Process exited with status 1