[Lazarus] Selection issues in class derived from TCustomDrawGrid

[Werner Pamler]

>>> When setting ExtendedSelect to true for the WorksheetGrid it works like expected

Yes, you are right - thanks. In fact, in my current version I already 
had the ExtendedSelect set to TRUE in the constructor but I had 
forgotten to update its default value in the property declaration as 
well. After doing this and deleting the FALSE from the lfm file it works 
now as expected.

I also fixed the ods bug with the empty sheet name - it was there all 
the time, but only detected after checking the sheet names...