es6-collections-iterators

Adds missing values, keys and entries functions to native es6 collection implementations

This especially concerns Internet Explorer 11, which implements es6 collections,
but does not implement the functions to retreive their elements via iterators
and Safari 7.1 and 8, which implement the functions but do not return a valid
iterator (the next method is missing).

This polyfill tries to fix this to make IE 11 and Safari 7.1 and 8 more
compliant with the current standard.

Usage


``js
require('es6-collections-iterators')
`

*Note that this polyfill only does something if the collections Set and Map
are available, but the respective prototype methods entries, keys and
values` are not implemented correctly.*