Litecoin support (todo list)

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• [x] doesn't check signature correctly for Litecoin
• [x] says making Bitcoin address when generating key
• [x] should highlight that it's a Litcoin Opendime (add their logo image somwhere?)

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• [x] maybe: add litecoin: url-scheme to QR code link

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• [x] needs different list of Litecoin explorers
• [x] search for other 'bitcoin' strings

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Didn't mean to push this yet but Litecoin support is on master now.