Error(s) in re-building vignettes:
  ...
--- re-building ‘custom_functions.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

randomForest 4.6-14
Type rfNews() to see new features/changes/bug fixes.

Attaching package: 'randomForest'

The following object is masked from 'package:ggplot2':

    margin

The following object is masked from 'package:dplyr':

    combine

Quitting from lines 49-59 (custom_functions.Rmd) 
Error: processing vignette 'custom_functions.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘custom_functions.Rmd’

--- re-building ‘grouped_forecast.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.
Loading required package: dplyr

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


Attaching package: 'xgboost'

The following object is masked from 'package:dplyr':

    slice

Quitting from lines 82-91 (grouped_forecast.Rmd) 
Error: processing vignette 'grouped_forecast.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘grouped_forecast.Rmd’

--- re-building ‘grouped_forecast_sequences.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.
Loading required package: dplyr

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


Attaching package: 'xgboost'

The following object is masked from 'package:dplyr':

    slice

Quitting from lines 83-95 (grouped_forecast_sequences.Rmd) 
Error: processing vignette 'grouped_forecast_sequences.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘grouped_forecast_sequences.Rmd’

--- re-building ‘lagged_features.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.
Loading required package: dplyr

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 29-37 (lagged_features.Rmd) 
Error: processing vignette 'lagged_features.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘lagged_features.Rmd’

--- re-building ‘package_overview.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.
Loading required package: dplyr

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

Loading required package: Matrix
Loaded glmnet 3.0-2

randomForest 4.6-14
Type rfNews() to see new features/changes/bug fixes.

Attaching package: 'randomForest'

The following object is masked from 'package:ggplot2':

    margin

The following object is masked from 'package:dplyr':

    combine

Quitting from lines 155-174 (package_overview.Rmd) 
Error: processing vignette 'package_overview.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘package_overview.Rmd’

SUMMARY: processing the following files failed:
  ‘custom_functions.Rmd’ ‘grouped_forecast.Rmd’
  ‘grouped_forecast_sequences.Rmd’ ‘lagged_features.Rmd’
  ‘package_overview.Rmd’

Error: Vignette re-building failed.
Execution halted