message: Clean up copy button code
diff: <div ng-show="showCtfFlagsInNotifications">
  <i class="fa fa-flag-checkered"></i> {{notification.flag}}
  - <button class="btn btn-primary btn-xs"
  - ngclipboard data-clipboard-text="{{notification.flag}}"
  - ngclipboard-success="notification.copyText = 'Copied!'"
  - >
  + <button class="btn btn-primary btn-xs" ngclipboard data-clipboard-text="{{notification.flag}}" ngclipboard-success="notification.copied = true">
  <i class="fa fa-clipboard" aria-hidden="true"></i>
  - <span translate="{{ notification.copyText ? 'COPY_SUCCESS' : 'COPY_TO_CLIPBOARD'}}"></span>
  + <span translate="COPY_SUCCESS" ng-show="notification.copied"></span>
  + <span translate="COPY_TO_CLIPBOARD" ng-show="!notification.copied"></span>
  </button>
  </div>
  </div>
  