"null" must be a quoted key in IE 6-8

Fixes #382
Add "unaryOperators" to utils module
Improve disallowSpaceAfterPrefixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Improve requireSpaceAfterPrefixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Add "iAndDecrementOperators" attribute to utils module
Improve disallowSpaceBeforePostfixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Improve requireSpaceBeforePostfixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Rename property in utils module

Switch to more meaningful name
Updating dependencies.
Vow has changed its Promise API to be more ES6-compliant.