title: How to config [mode]="'sql'" use ng2-ace-editor in angular 7?
body: <p>When I use ng2-ace-editor. have config </p>
  
  <pre><code>&lt;div ace-editor
         [(text)]="text"
         [mode]="'sql'"
         [theme]="'eclipse'"
         [options]="options"
         [readOnly]="false"
         [autoUpdateContent]="true" 
         [durationBeforeCallback]="1000"
         (textChanged)="onChange($event)"
         style="min-height: 20px; max-height: 20px; width:100%; overflow: auto;"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>But have console.log </p>
  
  <pre><code>http://localhost:4200/mode-sql.js net::ERR_ABORTED 404 (Not Found)
  http://localhost:4200/mode-html.js net::ERR_ABORTED 404 (Not Found)
  </code></pre>
  
  <p>How to config mode in ng2-ace-editor?</p>