feature: assets migrated from old repro

assets/reveal.js/plugin/math/plugin.js

@@ -0,0 +1,15 @@
+import {KaTeX} from "./katex";
+import {MathJax2} from "./mathjax2";
+import {MathJax3} from "./mathjax3";
+
+const defaultTypesetter = MathJax2;
+
+/*!
+ * This plugin is a wrapper for the MathJax2,
+ * MathJax3 and KaTeX typesetter plugins.
+ */
+export default Plugin = Object.assign( defaultTypesetter(), {
+	KaTeX,
+	MathJax2,
+	MathJax3
+} );