• Add methods xor() and xorNot() to the interface Spec (and implementations).

• Add class Xor and sugar function xor()
• Add class XorNot and sugar function xorNot()
• Change class members' visibility from private to protected

New

• Add syntax sugar. Update examples in README.md to show them.

Change

• Avoid unnecessary files from being published

New

• Add class Empty
• Add contributing.md

New

• New classes All and Any (by @sdedovic)

New

• New type definition for Spec
• New classes
  • StrictEqualTo
  • SameValueAs
  • StrictSameValueAs
  • SameTypeAs
• New tests

Upgrade development dependencies

Removes "_" from classes' names