Fixes #2964.

Summary/Motivation:

Driven by recent algorithmic developments of the PyROS preprocessor, this PR implements sweeping changes to the PyROS preprocessor subroutine and subproblem formulations/object structures.

Changes proposed in this PR:

Update PyROS as follows:

• Overhaul the preprocessor
  • Leverage decision rules and equality constraints to identify second-stage variables and state variables that are mathematically nonadjustable
  • More structured methods for reformulating variable domains/bounds to constraints
  • More structured methods for rearranging inequality constraints
  • Rewrite and extend coefficient matching: carefully account for state variable-independent constraints that cannot be reformulated by casting to inequality constraint pairs
• Update the subproblem formulations and modeling objects
  • Modify block structures of the working model, master-like models, and separation model: partition the constraints by stage
  • Change the objective of the decision rule polishing problem to the 1-norm of the nonstatic terms of the decision rule expressions
  • Perform more careful initialization of the auxiliary uncertain parameter variables of the separation problem
• Update the UncertaintySet class and pre-implemented subclasses to facilitate changes to the subproblems
  • Modify return protocol of UncertaintySet.set_as_constraint to make auxiliary uncertain parameters easier to track
  • Add new efficient methods for calculation of auxiliary uncertain parameter values for the CardinalitySet and FactorModelSet classes
  • Restrict range of valid FactorModelSet instances to those for which psi_mat is full column rank
  • Bug fix(es) for the IntersectionSet
• Logging updates
  • Make log of the model component statistics slightly more informative
  • Add DEBUG-level messages for logging of the individual preprocessor steps
• Documentation updates
  • Update "Methodology Overview" section
  • Add section on PyROS installation instructions
  • Adapt PyROS documentation to reorganized Pyomo documentation (post Reorganize online documentation #3382)
• Make tests more rigorous and extensive
  • Address Restore PyROS failed separation problem test #2964
  • Use expression comparison methods (core.expr.compare.assertExpressionsEqual) for more precise model testing
  • Separate testing modules for the:
    • preprocessor
    • subproblem formulations
    • uncertainty set classes
      • more rigorous testing for point_in_set, set_as_constraint
    • PyROS solver as a whole

TODO

• (After PR Add ParameterizedQuadraticRepn and corresponding expression walker #3324 merged) use ParameterizedQuadraticRepnVisitor in lieu of generate_standard_repn
• Update PyROS version number and changelog

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