Add maintainer

[v4hn]

@mjeronimo @sloretz @jacobperron @clalancette

I raised #259 over a month ago asking for a simple bloom release into noetic to fix rqt in the official noetic packages.

I mentioned the non-responsiveness concerning noetic talking to @arne48 and he offered to help with such quick maintenance tasks, but he needs access to the gbp repository to bloom.
Could either of you please add him to help?

Alternatively you might also transfer the kinetic-devel branch to ROS orphaned and give me access here to push a version commit before releasing. I don't care which option any one of you choose, but I would like to see this fixed very soon.