Updated all sample datasets to Google Genomics Public Data

For more information see [Google Genomics Public Data](https://cloud.google.com/genomics/public-data).
It would probably be easier to add a `data check` class where one of the methods does a `variantsets/search` on datasetId `3049512673186936334` and filters by `referenceName` with the chromosome number.  Then the appropriate reference string is returned.