Add Trezor to wallets

This pull request adds TREZOR to the list of wallets, enables the "Hardware" entry in the menus and drops the "soon-to-be-released" list of hardware wallets on the "Secure your wallet" page.

Live previews:
http://bitcointest1.us.to/en/choose-your-wallet
http://bitcointest1.us.to/en/secure-your-wallet