message: replace the :arrow_up: and :arrow_down: utf8 chars by their fontawesome version
diff: <jhi-route-selector></jhi-route-selector>
  - <div class="to-bottom" *ngIf="logtxt" (click)="scrollToBottom()">&#8675;Bottom</div>
  + <div class="to-bottom" *ngIf="logtxt" (click)="scrollToBottom()"><i class="fa fa-arrow-circle-down"></i> Bottom</div>
  <div class="form-group">
  <textarea #logfile readonly class="form-control log-viewer" rows="30">
  {{logtxt}}
  </textarea>
  </div>
  - <div class="to-top" *ngIf="logtxt" (click)="scrollToTop()">&#8673;Top</div>
  + <div class="to-top" *ngIf="logtxt" (click)="scrollToTop()"><i class="fa fa-arrow-circle-up"></i> Top</div>
  </div>
  