Integrate parallel gdal read (write is still serial)

[msl3v]

This PR is an update to a previous (closed) PR. This version of the code properly reads shapefile and features in parallel. It can write attributes to an existing shapefile (serial only) but cannot write the new shapefile.

[msl3v]

Jim, here's a simple question. If I make code updates and push them to the branch being merged with this PR, does the PR automatically update? or is the PR associated with a specific commit?

[jedwards4b]

@msl3v The PR automatically updates when you push to the PR branch.

[jedwards4b]

I suggest that you merge in the latest main to clear the out-of-date message.

[msl3v]

Hey @jedwards4b. This exact thing prompted my question. I HAVE updated, committed and pushed. But the PR didn't seem to update the log. If you look at the commit log for the actual branch in my repo, it's not the same as the one shown here in the PR.

It may be worth mentioning this: You prob know that ESMF doesn't keep PIO as a sub-repository. It's a frozen version that is copied into the ESMF source tree. That's where I do my development. And then have to wholesale copy my changes into an actual git-enabled version of PIO. I'd tried to make PIO a sub-repository in ESMF but it broke all sorts of things in the workflow. Maybe this can be remedied, but I don't know how to do it and it's not my call.