Merge branch 'citations' into 'NIFTy_5'

Add ascl citation to docs

See merge request !325
11 jobs for NIFTy_5 in 9 minutes and 23 seconds (queued for 1 second)
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  Build Docker
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build_docker_from_cache

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  Test
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test_mpi

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test_serial

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  Release
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pages

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  Demo Runs
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run_bernoulli

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run_curve_fitting

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run_ipynb

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  Deploy
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