render(elt, data, cur) {
    let icon = document.createElement('div');
    let text = document.createElement('div');
    let tail = document.createElement('div');
    icon.setAttribute("class", "icon " + this.completion.icon);
    text.setAttribute("class", "name");
    tail.setAttribute("class", "tail");
    text.textContent = this.completion.displayText;
    tail.textContent = this.completion.tail;
    elt.appendChild(icon);
    elt.appendChild(text);
    elt.appendChild(tail);
  }
Implementation of replacing text after choosing completion.

@param elt - node element
@param data
@param cur