Fix issues with overusing CSS :hover in the wallet page

Live preview: http://bitcointest2.us.to/en/choose-your-wallet

This pull request aims to fix issue #544

Wallets are only displayed on click when javascript is enabled (basic CSS compatibility is preserved)
(javascript applies a .nohover class on all wallets and then selectively add or remove this class with click and mouseout events)

Clicks in the menu now works for parents (Desktop/Mobile/Hardware/Web), so it's possible to lock selection to any platform, in such a way that accidental :hover on the menu will be reverted.