Update explorer

The explorer hosted at https://explore.ewatercycle.org/. When you select a "start experiment" you should get a notebook that uses the updated ewatercycle python package.

- Update the notebook template in https://github.com/eWaterCycle/experiment-launcher should be updated.
- Change the name of the notebook in https://github.com/eWaterCycle/terriajs and
- Change fetching the right datasets in https://github.com/eWaterCycle/TerriaMap
- Include wflow pcrglob and marrmot, and their example use cases.