1.3.0

What's new

- Is

• The Is contract takes a boolean expression value.
  Examples of using:

    string str = "string";
    Contract.Is<ArgumentNullException>(str != null);
    Contract.Is<ArgumentException>(str != "string"); // ArgumentException !!!

• The IsNot contract takes a boolean expression value and acts back to the contract Is
  Examples of using:

    string str = "string";
    Contract.IsNot<ArgumentNullException>(str != null); // ArgumentNullException !!!
    Contract.IsNot<ArgumentException>(str != "string");