Current time display wrong near DST change

[Cyrus Daboo]

The red line 'now' indicator in the day-week calendar display is off by one hour when close to a DST boundary. This is due to an incorrect algorithm for mapping from a UTC time to local timezone time. It takes the UTC time and determines whether it matches standard or daylight offsets. However, when the UTC is on one side of a DST change, and the local time is on the other, it picks the wrong offset. A better solution would be to subtract a 'base' offset first, then determine daylight or standard state, then readjust from there.