astropy/astropy — pull request #2968 by mhvk (2014-09-22 18:15:53+00:00)
Title: Quantity addition with zero

Adding a `Quantity` with 0 (or an array of zeros) removes the unit:
```
>>> (5. * u.electron) + 0.
5
```

The result is still a `Quantity`, but the `unit` is `None`. Is this a bug or a feature?