Error(s) in re-building vignettes:
  ...
--- re-building ‘sos4R-vignette-01-quickstart.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.
Quitting from lines 106-107 (sos4R-vignette-01-quickstart.Rmd) 
Error: processing vignette 'sos4R-vignette-01-quickstart.Rmd' failed with diagnostics:
Gateway Timeout (HTTP 504). Failed to sending request to SOS.
--- failed re-building ‘sos4R-vignette-01-quickstart.Rmd’

--- re-building ‘sos4R-vignette-02-ogc-sos.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 ‘sos4R-vignette-02-ogc-sos.Rmd’

--- re-building ‘sos4R-vignette-03-sos-operations.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.
Quitting from lines 107-108 (sos4R-vignette-03-sos-operations.Rmd) 
Error: processing vignette 'sos4R-vignette-03-sos-operations.Rmd' failed with diagnostics:
Gateway Timeout (HTTP 504). Failed to sending request to SOS.
--- failed re-building ‘sos4R-vignette-03-sos-operations.Rmd’

--- re-building ‘sos4R-vignette-04-extensions.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.
Quitting from lines 26-29 (sos4R-vignette-04-extensions.Rmd) 
Error: processing vignette 'sos4R-vignette-04-extensions.Rmd' failed with diagnostics:
Gateway Timeout (HTTP 504). Failed to sending request to SOS.
--- failed re-building ‘sos4R-vignette-04-extensions.Rmd’

SUMMARY: processing the following files failed:
  ‘sos4R-vignette-01-quickstart.Rmd’
  ‘sos4R-vignette-03-sos-operations.Rmd’
  ‘sos4R-vignette-04-extensions.Rmd’

Error: Vignette re-building failed.
Execution halted