Not obsolete anymore (yet again..?)

[NekR]

Obsolete polyfill for the ServiceWorker cache API. Chrome 46 and Opera 33 support addAll now.

I think this is wrong since addAll() gets new algorithm soon. I am not sure I can properly rephrase that sentence, so just creating an issue instead of PR.

Plus, you have to publish v4 to NPM :-)

[jakearchibald]

Published. Will look at the rewording.

[NekR]

Thanks!