fiona 1.8.0 bug breaks `datasets-identify.ipynb`

[jreiberkyle]

In datasets-identify.ipynb, we use fiona to read the shapefile coordinate reference system. The version of fiona that is associated with the version of rasterio we are using, 1.8.0, has a bug where it is unable to open the EPSG support file gcs.csv. This issue is documented here. In 1.8.1, this bug will be fixed. Wait for 1.8.1 to go live and fix the installed fiona to that version.

[sgillies]

@jreiberkyle a work around exists: always open and access Fiona collections within the context of a fiona.Env:

with fiona.Env(), fiona.open("example.shp") as collection:
    print(collection.crs)

[jreiberkyle]

Thanks @sgillies, will implement that workaround