+-- A PMConfig structure has a bunch of configuration values used by
+-- many functions in PMInstanceGenerator, ProposalMatcher, and Evaluation, which
+-- take a PMConfig as their first argument. Module PMDefaults defines a sane
+-- default configuration `pmDefaults'; it can be used as-is or individual fields
+-- can be overridden, e.g., pmDefaults{loadTolerance = 2} . See module
+-- PMDefaults for documentation of each field.