Continued a bit:

Continued a bit:
- random password generator massively improved:
- splitted alphabet string up in lower-case, upper-case, number and sign (aka. part)
- take random "part" and add char from it to random password
- also added calculation of password entropy value and password strength (0-100)
- this idea is based on:
  http://stackoverflow.com/questions/14591701/how-to-check-password-strength-in-vaadin
  http://stackoverflow.com/questions/1614811/how-do-i-measure-the-strength-of-a-password