Thread through the ability to allow grid objects to own memory

[Yurlungur]

PR Summary

This MR is on the path to supporting Sesame grids in singularity-eos. In this MR, I extend the spiner infrastructure so that Grid1D objects can own memory. This required extending the serialization routines and getOnDevice and finalize routines to call the appropriate grid objects as well. This ended up being a sufficiently sweeping change/large diff that I decided to split it out into a separate MR to get reviewed/tested by the CI.

One note I want to make that is an engineering decision that I'm not sure I want to keep: Usually we assume all operations in spiner are shallow. However, this "always shallow" model could get cumbersome if multiple databoxes each want to share Grid objects, which might themselves own array data. We have a few solutions to this:

1. Keep the model and aggressively insist that the user manage memory for Grid objects
2. Make grid objects use static memory or make them do deep copies

I chose path 1 for now. But I will at least revisit this decision in the subsequent MR when I add non-uniformly spaced grids for real.

PR Checklist

• Code is formatted. (You can use the format_spiner make target.)
• Adds a test for any bugs fixed. Adds tests for new features.
• Document any new features, update documentation for changes made.
• Make sure the copyright notice on any files you modified is up to date.
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If preparing for a new release, in addition please check the following:

• Update the version in cmake.
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