[Bf-python] semantic of the get function

[Jacques Guignot]

In the new python API, XXX.get() returns the list of the ***names*** of 
the XXX objects of the current scene.

In the old API, XXX.get() returns the list of the XXX objects of the 
current scene.

This feature will break the compatibility of the new API.

I strongly suggest we return to the old semantic, unless there is a 
***very good*** reason to change.

What do you think?