`Jenkinsfile` is used in Jenkins 2.0 for defining your pipeline as code.

See https://jenkins.io/doc/pipeline/jenkinsfile

Closes #4220

Closes #4188

Closes #4201

Closes #4190

Issue #4188

Closes #4185

Issue #4178

So f-strings get terminated correctly

Closes #4179

Issue #4176

Closes #4178

Closes #4166

Closes #4150

Closes #4152

Issue #3893

Closes #4140

Closes #4149

Closes #4147

Closes #4131

Closes #4130

Closes #4105

- Images now come with tons of information to style them. This mainly
  enables to style alt-texts and potentially make them look like links.
  While still differentialting between links and images.

Closes #4082

Closes #4085

It is, per https://golang.org/ref/spec#Predeclared_identifiers

Closes #4064.

Closes #3888
Closes #4063.

Closes #3796

Closes #3900

Closes #3926
Closes #4026

Add gutters properties (grid-gap, grid-column-gap and grid-row-gap):
https://www.w3.org/TR/css-grid-1/#gutters

Take advantage to add some missing keywors:
* grid and inline-grid: https://www.w3.org/TR/css-grid-1/#grid-containers
* dense: https://www.w3.org/TR/css-grid-1/#grid-auto-flow-property

It's been a while since the list of properties has been updated:
https://drafts.csswg.org/css-grid/#property-index

1. Mention multiplex as a dependency
2. Add ERB as a MIME-type

Closes #4020