In-memory conversion to ESMPy Mesh/LocationStream

[bekozi]

Create an ESMF.Mesh or ESMF.LocationStream from geometries. Requirements to keep in mind:

• Finding shared nodes
• Point = ESMF.LocationStream
• Line = ?
• Polygon = ESMF.Mesh
• Global/local indexing when parallel
• Support single element

Ping @jhamman, @rokuingh

[bekozi]

This is working for polygon geometry collections that do not have multi-geometries or interiors. We need to add multi-geometry break support to the ESMPy interface to allow this. @rokuingh is aware and is looking into it. Right now, break values work when reading from the ESMF Unstructured Format.

[bekozi]

We need to add multi-geometry break support to the ESMPy interface to allow this.

This was a bug on the ocgis end, but does need some TLC in the ESMPy mesh interface. Basically, the break values in addition to the element connectivity indices were getting one added when converting from 0-based to 1-based indexing. We probably need a has_multi flag for the ESMPy mesh creation.