595 Add option to drag start only from item icon.

[rluiten]

Add an option for drag an drop to only start a drag if you click onthe actual icon of file list entry rather than the name of the entry.
Would probably mean I leave drag and drop on as it would be much harder for me to do it by accident.

[rluiten]

I have inverted my previous opinion i think.

Now I want drag and drop to start form anywhere in the selected line not just the named item or icon.
I had not realised just how often I dragged items from FreeCommander to other applications, being limited to only starting on the entry name or icon is making it harder.

I also think the prompt option inside FreeCommander itself on left drop should stop most if not all my previous miss drags.