Nested hierarchy subsetting with inherited dimensions

[bekozi]

Deeply nested netCDF data structures with inherited dimensions are causing issues with dimension map nesting and dimension retrieval from metadata. The two main issues are:

1. Dimension map parametrization should match the nested location of the field. Only a single level of nesting works currently.
2. Inherited dimensions should be found by looking up levels until a match is located. Dimensions are expected to be at the current nest level currently.

Thanks to @kurinjiselvaraj for reporting.

[bekozi]

There is working dev code in the following branch: https://github.com/NCPP/ocgis/tree/i503-nested-subsetting