calendar object
This method will add a number of minutes to the minute property.
bool add_minutes(int minutes)
Parameters:
minutes
The number of minutes to add.
Return value:
true on success, false on failure.
Remarks:
A negative value in the minutes parameter will subtract minutes from the current minute.
Any number of minutes can be added or subtracted. The rest of the time will adjust accordingly.
Example:

    // Create a calendar and set it to October 7, 1767 at 09:00 and add 60 minutes.

    void main()
    {
    calendar test;
    test.set(1767, 10, 7, 9, 0, 0);
    test.add_minutes(60);
    alert("Date", "The date is "+test.weekday_name+", "+test.month_name+" "+test.day+", "+test.year+", at "+test.hour+":"+test.minute+":"+test.second);
    }