allow histograms and facets to work together (needs mods in ggplot2)
Merge branch 'master' of https://github.com/ropensci/plotly into xsm-hist-and-facets
add param for new (future) version of ggplot_build
Merge branch 'xsm-hist-and-facets' of https://github.com/ropensci/plotly into marianne-enhance-ggplotbuild
use our own ggplot_build function instead of ggplot2's
run roxygenize
run roxygenize again (to run github tests)
cleanup
remove update.plotly
cleanup