use make_ in `collection/filter` and `collection/map`, fixes #183

 - also use `lang/isInteger` in collection/size and `collection/make_` to avoid using array iterators on array-like objects with NaN values
 - all relevant unit tests were updated
 - some objects in unit tests were changed to use string values rather than numeric values: this is due to a shortcoming of jasmine's toEqual() which asserts true for {0: 1} and [1].