Fix for tasks to correctly show parent with child

[GrahamJB]

In the tasks view tasks were shown with the dots
indicating that the item above was it's parent - only it
usually was not.

This fix shows the parent(s) above the task if there is/
are any.

http://sourceforge.net/tracker/index.php?func=detail&aid=954916&group_id=21656&atid=372485

[GrahamJB]

I have just submitted a revised patch that impact 'My Tasks' etc.

It now only shows the parent item if it is missing from the list - this means that the project view now displays as before, but my tasks shows correctly, which it did not pre-patch.

[GrahamJB]

Also fixed bug where if no user was assigned column contents was missed and other columns contents moved one over.