Disallow different passwords for accounts

[honeycrypto]

Right now user can create new accounts with a different passwords. This may be very confusing UX because users will have to backup both passwords and private keys. Maybe we should force user to use same password as he used for created/imported account 0.

Since we don't store passwords, the flow can be as follows:

1. Ask for a password to create new account
2. Verify if this password can successfully decrypt address 0 from storage.
3. Throw error "Invalid Password" if user tried to use a new password.

Thoughts?