verify_password in 1.7.0 was no longer behaving like in 1.6.9

Maybe related to https://github.com/mattupstate/flask-security/issues/210

Simple experimental code with bcrypt no longer returned true:
```verify_password('psw', encrypt_password('psw'))```

Not sure if my fix is correct but at least the created tests started to pass and it's similar to how the latest verify_and_update_password works.

This pull request is against "develop", let me know if this is wrong and should be against some other branch.