Establish paradigm for configurable, automated visitor validation

[lbschanno]

Come up with a paradigm where checks for validity can be enabled on a visitor via configuration so that that they can be tested in production if it's suspected that an issue is occurring. This should include support for the following existing checks:

• Whether or not the resulting query tree has a valid lineage
• Whether or not the resulting query tree has an AND/OR node with fewer than 2 children.
  Additionally, the paradigm should have a focus on making it relatively straightforward to add new checks.

Originally mentioned in #1233 as part of #1236.