Merge branch 'feature-clarify-API-output_files_parameter' into 'develop'

Replacing all output_file occurences by output_files

See merge request !13
13 jobs for develop in 15 minutes and 7 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Ci
passed #12151
osx-10.13 sci
ci:osx

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passed #12150
ubuntu sci docker
ci:ubuntu_bionic

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ubuntu sci docker
ci:ubuntu_trusty

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passed #12149
ubuntu sci docker
ci:ubuntu_xenial

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passed #12152
windows-10 sci
ci:windows

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  Deploy
passed #12156
osx-10.13 sci
deploy:osx

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passed #12155
ubuntu sci docker
deploy:ubuntu_bionic

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passed #12153
ubuntu sci docker
deploy:ubuntu_trusty

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passed #12154
ubuntu sci docker
deploy:ubuntu_xenial

00:01:10

passed #12157
windows-10 sci
deploy:windows

00:03:18

 
  Clean
passed #12158
ubuntu sci docker
clean:docker

00:00:28

passed #12159
osx-10.13 sci
clean:osx

00:00:30

passed #12160
windows-10 sci
clean:windows

00:02:07