Improved Singletons - Implements #64

[benkirk]

After the discussion today I implemented Derek's idea with thread safety, and reimplemented RemoteElem on top of that. This should probably get pulled before the ReferenceElem business and I'll refactor that to use this.

Any issues?

Roy, what are your thoughts / issues regarding multiple LibMeshInit objects?

-Ben

[buildhive]

libMesh - C++ Finite Element Library » libmesh #391 SUCCESS
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[roystgnr]

This looks good upon first skimming.

Mostly my concern regarding multiple LibMeshInit objects is that I'd like to make it easy to couple multiple libMesh-using codes together without them having to be too aware of each other, even in the case where they both think they're responsible for initializing libMesh and they're not passing the same MPI communicator in. This isn't a near-term plan, just something I'm trying to keep in mind lest we make any API changes that might preclude doing it in the long-term.

[buildhive]

libMesh - C++ Finite Element Library » libmesh #392 SUCCESS
This pull request looks good
(what's this?)

[benkirk]

Merging this so I can rebase the ReferenceElem work off of it.