enable notes, search, menu and zoom plugins by default

reveal_plugins now defaults to c("notes", "search", "menu", "zoom");
pass NULL to render without plugins. Existing self_contained decks keep
working: the default set is dropped with a warning there instead of
triggering the hard stop, which still applies to explicitly requested
plugins.

Change-Id: I9041861a6914886e0c32ab5e37b8c4f55a5576c3
diff --git a/man/revealjs_presentation.Rd b/man/revealjs_presentation.Rd
index 0d291c2..c1c1ff2 100644
--- a/man/revealjs_presentation.Rd
+++ b/man/revealjs_presentation.Rd
@@ -19,7 +19,7 @@
   transition = "convex",
   background_transition = "fade",
   reveal_options = NULL,
-  reveal_plugins = NULL,
+  reveal_plugins = c("notes", "search", "menu", "zoom"),
   highlight = "default",
   mathjax = "default",
   template = "default",
@@ -84,9 +84,10 @@
 be passed, using plugin name as first level key (e.g \code{list(slideNumber = FALSE, menu = list(number = TRUE))}).}
 
 \item{reveal_plugins}{Reveal plugins to include. Available plugins include
-"notes", "search", "zoom", "chalkboard", and "menu". Note that
-\code{self_contained} must be set to \code{FALSE} in order to use Reveal
-plugins.}
+"notes", "search", "zoom", "chalkboard", and "menu". Defaults to
+\code{c("notes", "search", "menu", "zoom")}; pass \code{NULL} to render without
+any plugins. Note that \code{self_contained} must be set to \code{FALSE} in order
+to use Reveal plugins.}
 
 \item{highlight}{Syntax highlighting style passed to Pandoc.
 
@@ -233,7 +234,7 @@
 \dontrun{
 
 library(rmarkdown)
-library(revealjs)
+library(revealjs.ids)
 
 # simple invocation
 render("pres.Rmd", revealjs_presentation())