window.Intl cannot be assigned on Android 4.4

[mdwyer-od]

Using the Intl polyfill on Android 4.4 does not work (Intl.PluralRules specifically) because the Chrome version for Android 4.4 (v30) does not allow for window.Intl to be assigned. Could window.Intl.PluralRules be assigned directly instead?

https://github.com/wessberg/Polyfiller/blob/master/polyfill-lib/intl/intl.js#L5818

[mdwyer-od]

I created a PR for this here: #17