Issue on page /content/code_gallery/data_access_notebooks/2017-03-21-ERDDAP_IOOS_Sensor_Map.html

[MathewBiddle]

Let's update this to use http://erddap.sensors.ioos.us/erddap/index.html and query for oxygen data.

cc Jim Reagan at NCEI (GH handle TBD).

[ocefpaf]

@MathewBiddle please take a look at #97. While it was a bit awkward to re-write it to query oxygen instead of wave height, we did hit an interesting corner case. The server has two dataset_ids with for that query but the sensor map only shows one. More info the notebook.