More compact code for reading password

[jylitalo]

• Even if the user has entered -w -l foo:bar, python will ignore bar as a password and either read it with getpass() or read from stdin.
• "foo".split(':')[0] is no different from "foo:bar".split(':')[0]
• regardless how a user gives password, python should check that the user has given password
• python can use strip() to eliminate possible end-of-line character

The only slightly open topic that I can figure out is whether python should strip() password before python validates that the user has given a password or give him the option to use some whitespace to give an empty password.