js modules now have 'mjs' extension

assets/disk0/tvdos/include/example.mjs

@@ -0,0 +1,12 @@
+var testfun = function() { println("peekaboo!") }
+
+exports = {greet}
+
+/*
+
+Try in your user program:
+
+let m = require("A:/tvdos/include/example.js")
+m.greet()
+
+*/