Adding tutorial for transforming frames

[dhood]

I am interested in contributing a new tutorial that shows how to use the BufferInterface. Essentially an answer to this question but also explaining that in python you need to import, for example, tf2_geometry_msgs to avoid the error mentioned here.

First I would like to confirm that this tutorial doesn't exist already.

If so, what is the appropriate way to go about adding this tutorial? It seems that the code in the tutorials on the wiki is not being pulled from anywhere external.. should I just get the content approved here and then post it to the wiki?

[tfoote]

That would be great to have. Go ahead and add it to: http://wiki.ros.org/tf2/Tutorials I'd be happy to review it afterwards if you ping me.