R: Vignettes and other documentation

# Vignettes and other documentation

## Vignettes from package 'tidytext'

tidytext::tf_idf |  | Tidy Term Frequency and Inverse Document Frequency (tf-idf) | HTML | source | R code
tidytext::tidying_casting |  | Converting to and from Document-Term Matrices and Corpus objects | HTML | source | R code
tidytext::tidytext |  | Introduction to tidytext | HTML | source | R code
tidytext::topic_modeling |  | Tidy Topic Modeling | HTML | source | R code