Update to reveal.js 4.1.2 (#136)

- New tools/ script to manually keep step for updates
- Plugins are all updated
- Template update following latest Pandoc version
- updated README for documentation
- Help page updated 
- See other change in NEWS file
diff --git a/inst/reveal.js-4.1.2/css/theme/source/league.scss b/inst/reveal.js-4.1.2/css/theme/source/league.scss
new file mode 100644
index 0000000..ee01258
--- /dev/null
+++ b/inst/reveal.js-4.1.2/css/theme/source/league.scss
@@ -0,0 +1,36 @@
+/**
+ * League theme for reveal.js.
+ *
+ * This was the default theme pre-3.0.0.
+ *
+ * Copyright (C) 2011-2012 Hakim El Hattab, http://hakim.se
+ */
+
+
+// Default mixins and settings -----------------
+@import "../template/mixins";
+@import "../template/settings";
+// ---------------------------------------------
+
+
+
+// Include theme-specific fonts
+@import url(./fonts/league-gothic/league-gothic.css);
+@import url(https://fonts.googleapis.com/css?family=Lato:400,700,400italic,700italic);
+
+// Override theme settings (see ../template/settings.scss)
+$headingTextShadow: 0px 0px 6px rgba(0,0,0,0.2);
+$heading1TextShadow: 0 1px 0 #ccc, 0 2px 0 #c9c9c9, 0 3px 0 #bbb, 0 4px 0 #b9b9b9, 0 5px 0 #aaa, 0 6px 1px rgba(0,0,0,.1), 0 0 5px rgba(0,0,0,.1), 0 1px 3px rgba(0,0,0,.3), 0 3px 5px rgba(0,0,0,.2), 0 5px 10px rgba(0,0,0,.25), 0 20px 20px rgba(0,0,0,.15);
+
+// Background generator
+@mixin bodyBackground() {
+	@include radial-gradient( rgba(28,30,32,1), rgba(85,90,95,1) );
+}
+
+// Change text colors against light slide backgrounds
+@include light-bg-text-color(#222);
+
+
+// Theme template ------------------------------
+@import "../template/theme";
+// ---------------------------------------------