Added more non-standard tests

* `Date.prototype.toLocaleFormat`
* error `columnNumber`
* `__lookupGetter__`
* String generics
* `for each...in`
* Iterator
* `__iterator__`
* Generators (JS 1.8)
* Array comprehensions
* Generator comprehensions

Mostly it's to make it 1% more readable (the first time I misread '123' as a number literal, interpreting it as some kind of nonsensical slice index).