add wiki page presenting chunk options.
add wiki page presenting chunk options.

fboehm/cboettig_site,fboehm/labnotebook,fboehm/labnotebook,fboehm/labnotebook,antass/labnotebook3,fboehm/cboettig_site,antass/labnotebook3,fboehm/cboettig_site,antass/labnotebook3,fboehm/cboettig_site,fboehm/labnotebook,fboehm/labnotebook,fboehm/labnotebook,fboehm/cboettig_site