Add more dynamic settings.

[bluecamel]

This adds a few more dynamic settings. I had to fork arsdk-xml to change some command names, so generate.py is pointing to my fork. I imagine that you'll want to do this differently, but since arsdk-xml is pretty far ahead of the original commit, I'm not sure how you'd want to handle it. Maybe it makes sense to just put the xml file in parrot_arsdk?

I also added a script that automatically fixes the generated files and removed that section from the docs.

Let me know how you'd like to handle this and I'll make any needed changes. At the very least, I wanted to share this with others. It's pretty nice to be able to change white balance, saturation, and exposure with rqt_reconfigure.