BListView: Style fixes

* Rename kDoubleClickTresh to kDoubleClickThreshold
  and use floating point in rval
* Pointer (*) goes with type for property var
* Use {}'s for multi-line if conditional
* rename point to where (consistent with header and rest of IK)
* Explicitly compare with 0 for bitwise operator statements
* Rename InitiateDrag() params

headers/os/interface/ListView.h

@@ -126,8 +126,8 @@ public:
 
 	virtual void				SelectionChanged();
 
-	virtual bool				InitiateDrag(BPoint point, int32 itemIndex,
-									bool initialySelected);
+	virtual bool				InitiateDrag(BPoint where, int32 index,
+									bool wasSelected);
 
 			void				SortItems(int (*cmp)(const void*,
 									const void*));