Fix pull() to change the list instead of creating a new one

In Lodash, _.pull() can be called on an array without using the returned value, see the example here: http://lodash.com/docs#pull

Not as short, but more consistent with Lodash.
You can eliminate the `try/except` and `break` by doing this:

```python
while array.count(value) > 0:
    array.remove(value)
```