create module-functions page

Author: jderochervlk

data/sidebar_manual_latest.json

@@ -37,7 +37,8 @@
   ],
   "Advanced Features": [
     "extensible-variant",
-    "scoped-polymorphic-types"
+    "scoped-polymorphic-types",
+    "module-functions"
   ],
   "JavaScript Interop": [
     "interop-cheatsheet",

pages/docs/manual/latest/module-functions.mdx

@@ -0,0 +1,7 @@
+---
+title: "Module Functions"
+description: "Module Functions in ReScript"
+canonical: "/docs/manual/latest/module-functions"
+---
+
+# Module Functions