Indigo devel

Hi, 

In a project, I had to convert compressed images in a rosbag into an mp4 video. I am working on ros indigo on ubuntu 14.04, and I had to do some small modifications to your code to be able to perform this conversion.

If I well understood image_bag_processor only work for sensor_msgs::Image, now I have added some code to make it work with sensor_msgs::CompressedImageConstPtr.

Congratulation for this package, 

Regads, 
Adrien BARRAL