print.ggvis: View in a ggvis plot in the browser.
In rpruim/ggvis2: Interactive grammar of graphics

view_static creates a static web page in a temporary directory; view_dynamic generate a dynamic shiny app and launches it. print automatically picks between the two.

## S3 method for class 'ggvis'
print(x, dynamic = NA, launch = interactive(), ...)

view_static(x, plot_id = rand_id("plot_"), dest = tempfile(pattern =
  "ggvis"))

view_dynamic(x, plot_id = rand_id("plot_"), port = NULL, quiet = FALSE)

`x`	A ggvis object.
`dynamic`	Uses `view_dynamic` if `TRUE`, `view_static` if `FALSE`. The default, `NA`, chooses automatically based on the presence of reactives or interactive inputs in `x`.
`launch`	If `TRUE`, will launch plot in a viewer/browser. If `FALSE` returns an object that you can `print()` to launch.
`...`	Other arguments passed on to `view_dynamic` and `view_static` ?from `print`.
`plot_id`	Unique identifier used to identify the plot on the page.
`dest`	Directory in which to save html and depedencies. Created if it doesn't already exist.
`port`	the port on which to start the shiny app. If NULL (the default), Shiny will select a random port.
`quiet`	If `TRUE` show status messages from Shiny. (Default is `FALSE`.)