Allow multiply and divide for two Angle objects?

I just ran into this error:
```python
>>> from astropy.coordinates import Angle
>>> field_of_view = Angle(10, 'deg')
>>> pixel_size = Angle(0.1, 'deg')
>>> n_pix = int(field_of_view / pixel_size)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/deil/Library/Python/2.7/lib/python/site-packages/astropy-0.4.dev7605-py2.7-macosx-10.9-x86_64.egg/astropy/coordinates/angles.py", line 208, in __div__
    type(self).__name__))
TypeError: division is not supported between two Angle objects
```

Should we change this so that multiply and divide for two Angle objects returns a Quantity object?
Or is there a reason this is a bad idea?