Add Drive export and import method

[aazuspan]

This would add two methods allowing ee.ImageCollection and its subclass objects to be exported to a Drive and then imported into an xarray.Dataset. Dimension and coordinates would be stored in filenames and parsed on import. This feature would allow users to handle time series data when file size or grid size is too large or computations time out.

Planned usage reference:

ts = wxee.TimeSeries("IDAHO_EPSCOR/GRIDMET").filterDate("2020", "2021")
task = ts.wx.to_drive(crs="EPSG:5070", scale=4_000)

# Once files are exported, user manually downloads them to a local folder
data_dir = "data"

ds = wxee.load_dataset(data_dir)

Drive exporting will be very similar to the wxee.image._get_url method but will instead run and return a batch export task. All of the importing functionality is already implemented in the private wxee.utils._dataset_from_files, so that portion should be simple.

[aazuspan]

This is more complicated because the ee.batch.Export.image.toDrive method has no filePerBand option, unlike getDownloadURL, and the _dataset_from_files function requires one file per band. The _dataset_from_files function will have to be adjusted to allow multiband files.

At that point, I need to decide whether to adjust TimeSeries.to_xarray to run with multiband files for consistency or leave as is with some methods using multiband files and others using file-per-band...

[aazuspan]

I'm closing this as out of scope. There are existing tools for exporting image collections to drive and loading a set of images into an xarray.Dataset is pretty straightforward, so I don't think wxee adds enough utility here to be worth pursuing.