Opera support

[Tox86]

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[Tox86]

Opera, Blink, Chrome, etc..

[nmaier]

Chrome is tracked elsewhere: #35

But it might be a good idea to officially support Opera, make sure it works there and publish in their add-on store.

[nmaier]

Ok, I tested the Chrome version with Opera, and it works reasonably well, so here it is: https://addons.opera.com/en/extensions/details/downthemall/

[Tox86]

Testing...

[nmaier]

Live on the homepage.