Which SDFormat corresponds to version of Gazebo
I've searched around and its not clear which version of the SDF spec (1.4-1.6) corresponds to Gazebo7, etc. My Ubuntu 16.04 package manager says I have SDFormat4 install, further confusing me. Why isn't the binary release matching the spec version?
From the Gazebo changelog, it seems Gazebo7 uses 1.6, but its not 100% clear. Perhaps this can be added to the documentation/website somewhere?