Updates API call 

When using the SDK and consulting this example app, one thing I found really confusing was how to properly construct the API call. I think this is in part due to the fact that there's a lot of similarity to the table name and the columns being queried. 

In light of completely changing the example, I clarified how the call is formed, with the location of the dataset followed by the table name. I also added a link to the dataset being used. 
I also cleaned up the file a bit, deleting some of the extra white space. 

:sparkling_heart: