New feature: "Warn patrons when their account is about to expire"
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To give staff the ability to warn patrons when their account is about to
expire, the staff client can display an alert message on the patron information
window.  A new library setting, `Warn patrons when their account is about to
expire` in the *Circulation* section of the *Library Settings Editor*,
determines how many days in advance of a patron's account expiry date the alert
should be displayed. By default, warnings about upcoming patron account expiry
dates are not displayed.