Support .mjs files

[maierfelix]

Is this a BUG or a FEATURE REQUEST?:
Feature Request (or bug?)

What happened:
Unable to run .mjs file, error is:

(function (exports, require, module, __filename, __dirname) { import fs from "fs";
                                                                     ^^
SyntaxError: Unexpected identifier
    at new Script (vm.js:73:7)
    at createScript (vm.js:245:10)
    at Object.runInThisContext (vm.js:297:10)
    at Module._compile (internal/modules/cjs/loader.js:657:28)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
    at Module.load (internal/modules/cjs/loader.js:599:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
    at Function.Module._load (internal/modules/cjs/loader.js:530:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:742:12)
...

What you expected to happen:
Not dat

How to reproduce it (as minimally and precisely as possible):
Create index.mjs:

import fs from "fs";
// bla

Bundle with:

nexe --input index.mjs --output test.exe --verbose --target windows-x64-10.9.0 --flags ["--experimental-modules"]

Environment

• Platform(OS/Version): Windows 10 x64
• Host Node Version: v11.9.0
• Target Node Version: v10.9.0
• Nexe version: nexe 3.0.0-beta.15
• Python Version: 2.7.15

Edit: I'm using pre-built v10.9.0 binary from releases

[calebboyd]

I think I will implement this using esm instead of the node flag. I don't really want to write much code around the .mjs file type...

[maierfelix]

@calebboyd any updates on this?

[calebboyd]

Closing in favor of #815