Merge branch 'improve_minimization' into 'NIFTy_4'

Improve minimization

See merge request ift/NIFTy!230
3 jobs for NIFTy_4 in 15 minutes and 33 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #510979
pages

00:06:27

passed #510978
test_min

00:15:33

67.0%
 
  Deploy
passed pages:deploy

00:00:00