Compare Pane - sorting improvements

... when sorting first and adding new items, table view is partly empty and when you next click on an item GC dumps (fixed by de-activating the sorting while refreshing the Table-Data  / sortingEnablement=true triggers sorting to be doen - and since the selected sorting column is still active from before - this seems to be a problem)
... date fields did not sorted due to different formats strings used in "toString" and "fromString" conversion / corrected the format and added info to translators 
... duration and time fields did - dependent on the values - not sort properly (e.g. in cases where time/duration having partly have hours or partly only minutes)