adds Function.prototype.name polyfill

http://people.mozilla.org/~jorendorff/es6-draft.html#sec-name
I don't see the ```'anonymousFn'``` in the current spec but just looked at the current chrome and firefox and they both return ```''``` so perhaps that's what it should do in this scenario?

The scope is for browsers like IE that don't yet have ```Function.prototype.name```