Merge branch 'add_useful_error' into 'NIFTy_4'

Add error message to MultiDomains

See merge request ift/NIFTy!267
5 jobs for NIFTy_4 in 9 minutes and 46 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build Docker
passed #626784
build_docker_from_scratch

00:07:28

 
  Test
passed #626785
test_python2_with_coverage

00:01:18

80.0%
passed #626786
test_python3

00:01:09

 
  Release
passed #626787
pages

00:00:59

 
  Deploy
passed pages:deploy

00:00:01