add into(DataFrame, pytables Table)

An addition to `into` so that one can go directly from a pytables Table to a pandas DataFrame.
with pytest you can use straight up assertions rather than going through the `TestCase` methods, it figures out what you're doing with some ast analysis and will be as informative as if you had used the `TestCase` methods. This would then become

```python
assert len(final) == 1
```