title: Package-lock.json - requires vs dependencies
body: <p>In package-lock.json in dependency object, I have both <code>requires</code> and <code>dependencies</code> fields, e.g</p>
  
  <pre><code>  "requires": {
      "@angular-devkit/core": "0.8.5",
      "rxjs": "6.2.2",
      "tree-kill": "1.2.0",
      "webpack-sources": "1.3.0"
    },
    "dependencies": {
      "rxjs": {
        "version": "6.2.2",
        "resolved": "https://registry.npmjs.org/rxjs/-/rxjs-6.2.2.tgz",
        "integrity": "sha512-0MI8+mkKAXZUF9vMrEoPnaoHkfzBPP4IGwUYRJhIRJF6/w3uByO1e91bEHn8zd43RdkTMKiooYKmwz7RH6zfOQ==",
        "dev": true,
        "requires": {
          "tslib": "1.9.3"
        }
      }
    }
  </code></pre>
  
  <p>What is the difference between these two? Why some dependencies are listed in <code>requires</code>, other in <code>dependencies</code>, and some of them in both of these fields?</p>