New icons and updated links.txt.

Change-Id: Ibdc0ba550b07e88bfd7798da028cf59315295c89
Reviewed-on: https://gerrit.libreoffice.org/41024Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>