Add option to allow Lumberjack to own communicator

[gberg617]

Summary

• This PR is a feature
• This PR adds the ability for Lumberjack to directly own a Communicator object. When this case is true, Lumberjack will call delete on the communicator object when finalize() is called.

[rhornung67]

setCommunicator() method needs to be added. Also, should initialize() check to make sure it's not being called more than it should? @white238 any additional comments?

[gunney1]

Looks okay to me pending the comment of @white238 .

[gberg617]

To Address comments from @white238, the following were added to this PR:

1. Methods in Lumberjack to get and swap communicators, as well as a getter for the isCommunicatorOwned flag.
2. isInitialized flag added to enforce initialize() to be called only once per Lumberjack instance.
3. Unit tests to check correct behavior for swapping owned and non-owned communicators in Lumberjack
4. Documentation
5. Release notes

[bmhan12]

4. Documentation

👍
Updated documentation for this PR can be found here: https://axom.readthedocs.io/en/feature-bergel1-lumberjack_set_communicator/axom/lumberjack/docs/sphinx/lumberjack_class.html

[rhornung67]

Please add setCommunicator(). Actually, if setCommunicator() returned existing communicator, then swapCommunicator() would not be needed.

[gberg617]

Please add setCommunicator(). Actually, if setCommunicator() returned existing communicator, then swapCommunicator() would not be needed.

@rhornung67 I changed the name of swapCommunicator to setCommunicator. It really does a set and not a swap, so the new naming makes more sense. A swap would probably involve passing in another Lumberjack object, and swapping its communicator with the current one (or something along these lines). I don't currently implement this type of functionality. Would it be useful at all to add it in? Doing a swap may be somewhat challenging because we would have to specially handle cases where Lumberjack owns the communicator.

[rhornung67]

@gberg617 my preference is to just go with setCommunicator for now. If we need a swap method at some point, we can deal with it then.

[kennyweiss]

Thanks @gberg617

[kennyweiss]

Should this function allow the user to indicate if the new communicator is owned?

[gberg617]

I added a bool flag to allow the user to set the ownership of the communicator passed in. I am assuming that the user has to set the ownership flag (i.e. it's not an optional parameter). Let me know if there are any issues with this.