Having a deactivated image selected disables the widgets to change its properties. For functional images they are enabled if an active functional image is selected.

* check if scipy version is < 0.18.0 before computing the different offset,
* shape is a tuple of integers (previously floats that were cast; integers are safer for the future).

added support for loading new (nifti-type) objects directly from the interactive shell, i.e., viewer.loadNewImageObject(fileobj, filename)