Additional comparisons are complete

The original spec by Eric Evans and Martin Fowler recommend the following additional comparisons:

• isSpecialCaseOf
• isGeneralizationOf
• remainderUnsatisfiedBy (CompositeSpecification)

Composite Immutability

Ensures that CompositeSpecification is both extensible and immutable. (Dart should have better visibility support.)

Initial release

v1.0.0

v1.0.0