Refactor case 1 notebook to v1 ewatercycle api (#19)

* First refactor pass without running

* Got it working till set_value

* Got to 3/4 of model run

* Dont use xarray for single point

* Notebook ran till end, but simulated discharge is too low

* Ran formatter on nb

https://github.com/ryantam626/jupyterlab_code_formatter

* Use csv instead of hdf

As hdf required table package to be installed and I did not want to restart again.

* Use one grid pixel above grdc station

* Add read_csv args

Author: sverhoeven