Fix to make `from pylifx import *` work.

Reported in https://github.com/derkarnold/pylifx/issues/1#issuecomment-36403362

Before:

```pycon
>>> from pylifx import *
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'pylifx'
```

After:

```pycon
>>> from pylifx import *
>>>
```