Image tutorial notebook edit

Make the Image tutorial more friendly to people using the IPython notebook to follow along (avoid use of set_xxx functions, use arguments to imshow instead.)

Also:
- use scipy.ndimage for image resizing in last example (interpolation)
- minor grammar fixes
- add notes about keeping plt commands in one cell so that effects are shown.
@tacaswell yes I think that is a second argument but the zmq text console and qt console could also be multi language and here it still works in the master build that I have. In any event this tutorial will be simpler if it uses %matplotlib which should work in all IPython variations.