Was used in Ubuntu formerly, but they now switched to breeze.

Human is mostly similiar to Tango, with some Ubuntu colors.
So it should be enough to keep Tango.

Change-Id: Ib44cbefb2953406c95dbb269ada663bce2503234
Reviewed-on: https://gerrit.libreoffice.org/29537
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Heiko Tietze <tietze.heiko@googlemail.com>
Tested-by: Yousuf Philips <philipz85@hotmail.com>
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>
Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>