Error(s) in re-building vignettes:
  ...
--- re-building ‘adding-tidiers.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘adding-tidiers.Rmd’

--- re-building ‘available-methods.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Joining, by = "class"
Joining, by = "class"
--- finished re-building ‘available-methods.Rmd’

--- re-building ‘bootstrapping.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘bootstrapping.Rmd’

--- re-building ‘broom.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
Warning in wilcox.test.default(x = c(3.215, 3.44, 3.46, 3.57, 3.19, 3.15,  :
  cannot compute exact p-value with ties
--- finished re-building ‘broom.Rmd’

--- re-building ‘broom_and_dplyr.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Quitting from lines 42-46 (broom_and_dplyr.Rmd) 
Error: processing vignette 'broom_and_dplyr.Rmd' failed with diagnostics:
there is no package called 'digest'
--- failed re-building ‘broom_and_dplyr.Rmd’

--- re-building ‘kmeans.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘kmeans.Rmd’

SUMMARY: processing the following file failed:
  ‘broom_and_dplyr.Rmd’

Error: Vignette re-building failed.
Execution halted