Added deprecated absolute() function for backwards compatibility.
Added deprecated absolute() function for backwards compatibility.

Review: https://reviews.apache.org/r/71961/

kaysoky/mesos,dforsyth/mesos,reneploetz/mesos,Gilbert88/mesos,Gilbert88/mesos,abudnik/mesos,reneploetz/mesos,Gilbert88/mesos,reneploetz/mesos,kaysoky/mesos,abudnik/mesos,abudnik/mesos,dforsyth/mesos,kaysoky/mesos,reneploetz/mesos,dforsyth/mesos,abudnik/mesos,abudnik/mesos,dforsyth/mesos,abudnik/mesos,dforsyth/mesos,reneploetz/mesos,dforsyth/mesos,kaysoky/mesos,kaysoky/mesos,Gilbert88/mesos,Gilbert88/mesos,reneploetz/mesos,kaysoky/mesos,dforsyth/mesos,reneploetz/mesos,Gilbert88/mesos,kaysoky/mesos,Gilbert88/mesos,abudnik/mesos