Add supporting themes required for Lotusdocs

themes/hugo-mod-jslibs-dist/popperjs/README.md

@@ -0,0 +1,12 @@
+```toml
+[[module.imports]]
+path="github.com/gohugoio/hugo-mod-jslibs-dist/popperjs/v2"
+```
+
+With that you can import it in your JS like this:
+
+```js
+import * as Popper from "@popperjs/core";
+```
+
+Note that this module was originally added for https://github.com/gohugoio/hugo-mod-bootstrap-scss