Adds tests related to IsInstanceOf() for Version type.
Now, the assertion method: 'InheritsFrom' is negatable.
Makes all methods of BooleanFluentAssertionExtensions negatable.
Updates the documentation to explain how to make the assertion methods compliant with the Not operator.
Makes all methods of ComparableFluentAssertionExtensions negatable.
Makes all methods of DateTimeFluentAssertionExtensions negatable.