[sponsor needed] Update sdformat to version 2.0.0

[Jose Luis Rivero]

Hi all:

I would need an sponsor to upload the major update of sdformat to
version 2.0.0. Speaking about the debian side of the update, it closes
the RC bug #74381 and enable the test suite.

http://anonscm.debian.org/gitweb/?p=debian-science/packages/sdformat.git;a=summary

As a side note, it is the only missing dependency to start the packaging
work of one of our most used simulator in robotics, gazebo.

Thanks.

-- 
Jose Luis Rivero <jrivero at osrfoundation.org>