Merge branch 'more_docs' into 'NIFTy_8'

Move custom nonlinearities to html docs

See merge request !668
15 jobs for NIFTy_8 in 20 minutes and 49 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Static Checks
passed #1370259
check_no_asserts

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  Build Docker
passed #1370260
build_docker_from_cache

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  Test
passed #1370262
test_mpi

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passed #1370261
test_serial

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86.0%
 
  Demo Runs
passed #1370270
run_bernoulli

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passed #1370271
run_curve_fitting

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run_getting_density

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passed #1370265
run_getting_started_1

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run_getting_started_2

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passed #1370267
run_getting_started_3

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passed #1370268
run_getting_started_mf

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passed #1370263
run_ipynb0

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passed #1370264
run_ipynb1

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passed #1370273
run_meanfield

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passed #1370272
run_visual_vi

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