Initial MIR component

[BradWhitlock]

This PR is adds an initial MIR component to Axom. EquiZ MIR was implemented as the first algorithm because it was more familiar and my first goal was to shake out problems with infrastructure for writing algorithms against Blueprint data. The MIR algorithm takes Blueprint input and generates Blueprint output.

This PR does the following:

• Supercedes previous MIR work (previous work was either adapted or moved to "reference" directory)
• Implements EquiZ (without iteration for now) that runs on CPU/GPU and works on 2D/3D meshes with various topology and shape types.
• Provides views to simplify writing algorithms that use Blueprint data.
• Provides several utility classes that perform mesh operations (extract zones, merge meshes, etc.)
• Adds documentation
• Adds example programs
• Adds a little core infrastructure

NOTE:

• The Elvira algorithm will be added in a future PR.
• The previous serial MIR implementation was moved to a "reference" directory that we can remove once EquiZAlgorithm has iteration support (future work).
• The component requires Conduit, RAJA, Umpire - I'll probably have to iterate with the CI some to make that work everywhere.
• There are some files that changed because of "make style"