picking in obspy.core.stream object Qt frontend

Hi guys! :)

after looking for a decent picking program last week, the only good option I found was ObsPyck which is kind of a big suite and unfortunately doesn't fit well into an existing ObsPy environment.
I decided to take a couple days, get into Qt and throw together a leightweight picking GUI, interfacing ``obspy.core.Stream`` and the ``obspy.core.event`` API (therefor QuakeML).

IMO these objects are far more easy to handle than any abstract text format like from sac or PQL.

* Reading ``obspy.core.Stream`` and ``obspy.core.event.Pick``

```python
cat = readEvents('events.xml')
new_pick = st.pick(picks=cat[0].picks)

print new_pick.picks
>>> List of obspy.core.event.Pick() objects
```

* Saving/reading QuakeML files through the interface, saving plot as image.

* Stream's slides are grouped by stations name (3C per slide)

* Simple filter management

![streampick-gui](https://f.cloud.github.com/assets/4992805/1061001/9baee60e-11c0-11e3-9cc3-2027a73954ae.png)

![streampick-about](https://f.cloud.github.com/assets/4992805/1046392/a34e6762-103b-11e3-97cd-e84e969660ae.png)

The question for me is now whether a Qt module fits into ObsPy.

cheers,

Marius