Node.js: a shim for overriding "http" and "websocket" modules.

Also added stubs for Server.address()
This was done to prevent crashes in some popular frameworks like express

Supports both CommonJS and the new ES Modules system syntax e.g:

app.js:
const http = require('http')

app.mjs:
import http from "http"

Usage on Node 14.16.x and higher:
{
    "type": "external",
    "processes": {"spare": 0},
    "working_directory": '/project',
    "executable": "/usr/bin/env",
    "arguments": [
        "node",
        "--loader",
        "unit-http/require_shim.mjs"
        "--require",
        "unit-http/require_shim",
        "app.js"
    ]
}

Usage on Node 14.15.x and lower:
{
    "type": "external",
    "processes": {"spare": 0},
    "working_directory": '/project',
    "executable": "/usr/bin/env",
    "arguments": [
        "node",
        "--require",
        "unit-http/require_shim",
        "app.js"
    ]
}

docs/changes.xml

@@ -31,6 +31,12 @@ NGINX Unit updated to 1.24.0.
          date="" time=""
          packager="Andrei Belov <defan@nginx.com>">
 
+<change type="feature">
+<para>
+a shim for automatic overriding "http" and "websocket" modules in Node.js.
+</para>
+</change>
+
 <change type="feature">
 <para>
 ability to limit serving of static files by MIME types.