Fix for issue 35: Display full Start/End time to the microsecond

Start/end times in the tree will appear as elided text, i.e. '2015.312.09:39.00.000000' will appear as '2015.312.09:39...'. The user can either double click the cell or hover over it to see the full times. The same will also be true for the split channels dialogue window. The right panel will always show the full times to the microsecond.