Setting the password for a created user

[verenadiewald]

The way it works now: The administrator user is the one who creates a new user and defines the new user's password by typing in a password. The new way could be:

• The administrator user creates a user without manually setting the password -> A generated one-time password is created dynamically and stored in the password field.
• When the new user's data is written to the mb_user table simultaneously a ticket number for that new user is written into table mb_user (new field)
• An e-mail is sent to the new user which contains a link to a new Mapbender module. The new module is a simple form where the user is requested to insert her new password (twice for confirmation), password is validated for safety
• If the ticket number is not valid the module returns an error
• If the ticket number is valid, the new password will be saved in db and the ticket number of this user will be deleted

[verenadiewald]

regular expression for password validation: [a-zA-Z0-9]{8,}