Name change reports changing from X to X

[Juan Pablo Caram]

When changing the name of an object, the status bar reports changing from X to X instead of X to Y.

[Juan Pablo Caram]

on_activate_name() was being called multiple times because every time a new object was created it registered the event again. Obviously after changing the name once, subsequent runs will display no change in name.

[Juan Pablo Caram]

For Geometry objects it was also connected from the Glade file.