title: how to create and use a new Build configuration in Angular CLI?
body: <p>In my <strong>Angular.json</strong> file. I have </p>
  
  <pre><code>      "configurations": {
          "production": {
            "fileReplacements": [
              {
                "replace": "src/environments/environment.ts",
                "with": "src/environments/environment.prod.ts"
              }
            ],
            "optimization": true,
            "outputHashing": "all",
            "sourceMap": true,
            "extractCss": true,
            "namedChunks": false,
            "aot": true,
            "progress": true,
            "buildOptimizer": true,
            "budgets": [
              {
                "type": "initial",
                "maximumWarning": "2mb",
                "maximumError": "5mb"
              }
            ]
          }
        }
  </code></pre>
  
  <p>This is executed when i run <code>ng build --prod</code></p>
  
  <p>How can I create a new configuration e.g. dev ? </p>