While CSS/JS assets can be set via the css/js keys under the meta field
of the html output format in YAML, this function provides another way to
add them, which can be called in a code chunk to dynamically add assets.
Usage
vest(feature = NULL, css = NULL, js = NULL)
Value
A vector of <link> (CSS) or <script> (JS) tags.
Arguments
feature
A character vector of features supported by CSS/JS, e.g.,
c('article', 'callout'). See the row names of litedown:::assets for all
available features. Each feature will be mapped to CSS/JS.