Update Effort#event_start_time so that attributes['event_start_time'] returns a TimeWithZone object.
Update Effort#event_start_time so that attributes['event_start_time'] returns a TimeWithZone object.

voltagead/OpenSplitTime,SplitTime/OpenSplitTime,voltagead/OpenSplitTime,voltagead/OpenSplitTime,SplitTime/OpenSplitTime,SplitTime/OpenSplitTime