DOC: Update README.MD to reflect TOBAC is not just for clouds

[scollis]

First, I am not suggesting a name change. I worry that folks might be dissuaded from using for radar based objects and other objects by the description. Once TINT is fully integrated (TINT Is Now TOBAC) we should update the readme. We can add some narrative like "Initially designed to track clouds, TOBAC is now used to track a variety of objects in datasets including..... "