Update copyright year.
Merge branch '1.3.x'
Added support for proof production in Equality Engine.  Cleaned up existing proof signatures and added proof signature for theory of arrays.  Added new MBQI technique based on interval abstraction.  Cleaned up option names.  Improved symmetry breaking for uf strong solver.  Other minor cleanup.
Removing and consolidating options for uf-ss and quantifiers.  Bug fix for inst gen-style MBQI.
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