Rohansi/Mond — pull request #8 by Syke94 (2014-09-30 10:33:18+00:00)
Title: Adds two new operators.

* Adds the `!in` operator as a convenience over the more verbose `!( x in y )`.
* Borrows the null coalesce operator from C#. `??` will check if a value is null or undefined.
* Adds tests for the new operators.