Update to reveal.js 4.6.1

Change-Id: I566737c50b93dd8c094ad3c3fa59865260b3b4ba
diff --git a/inst/reveal.js-4.6.1/plugin/customcontrols/style.css b/inst/reveal.js-4.6.1/plugin/customcontrols/style.css
new file mode 100644
index 0000000..88be439
--- /dev/null
+++ b/inst/reveal.js-4.6.1/plugin/customcontrols/style.css
@@ -0,0 +1,70 @@
+#customcontrols {
+	z-index: 40;
+	position: fixed; 
+	left: 70px; 
+	bottom: 30px;
+	text-align: center;
+	font-size: 24px;
+}
+
+#customcontrols button {
+	background: none;
+	color: var(--r-link-color);
+	border: none;
+	padding: 0;
+	font: inherit;
+	cursor: pointer;
+	outline: inherit;
+	z-index: 40;
+}
+
+#customcontrols button:hover {
+	color: var(--r-link-color-hover);
+}
+
+#customcontrols > ul {
+	position: fixed; 
+	left: 54px; 
+	bottom: 64px;
+	list-style-type: none;
+	overflow: hidden;
+	margin: 0;
+	border: 1px solid var(--r-link-color);
+	border-radius: 5px;
+	padding: 10px;
+	background-color: var(--r-background-color)
+}
+
+#customcontrols ul > li {
+	margin: 0px 5px;
+	padding: 0px 5px;
+	float: left;
+}
+
+#customcontrols.collapsed  #collapse-customcontrols, #customcontrols.collapsed > ul  {
+	display: none;
+} 
+
+#customcontrols:not(.collapsed) #expand-customcontrols {
+	display: none;
+} 
+
+@media only screen and (min-width: 500px) {
+	#customcontrols > button {
+		display: none;
+	}
+	#customcontrols > ul {
+		padding-top: 0px;
+		padding-bottom: 0px;
+		bottom: 30px;
+		border: none;
+		background: none;
+	}
+}
+
+@media print {
+	#customcontrols {
+		display: none!important; 
+	}
+}
+