Decide between ROS & Python

[asmodehn]

We need to make up our mind if this package is :

• a python package, ported to ROS
• a ROS package, ported to Python

Because the release workflow is a bit different, and it needs to be documented.

Also the usage workflow is a bit different ( and both ROS and python over ROS way could be useful ).
Both usage should probably be documented...

[asmodehn]

I think the workflow of THIS package should be :
1 try to use a system distribution (with pyros-setup, the way it works now).
2 If not found, fallback on an embedded pure python ROS package suite (it is in one of the pyros package somewhere... need to track it down...) The point of #14

[asmodehn]

And it is therefore, to respond to the question, a python package (eventually ported to ROS - but can be used from pure python package, with ROS tooling).