Remove Cocoa code and precompiler defines targeting OS X versions prior to OS X 10.7.

include/wx/osx/cocoa/dataview.h

@@ -249,7 +249,7 @@ private:
 // owned by the set. Furthermore, children of the last parent are stored
 // in a linear list.
 //
-@interface wxCocoaOutlineDataSource : NSObject wxOSX_10_6_AND_LATER(<NSOutlineViewDataSource>)
+@interface wxCocoaOutlineDataSource : NSObject <NSOutlineViewDataSource>
 {
     // descriptors specifying the sorting (currently the array only holds one
     // object only)
@@ -395,7 +395,7 @@ private:
 // wxCocoaOutlineView
 // ============================================================================
 
-@interface wxCocoaOutlineView : NSOutlineView wxOSX_10_6_AND_LATER(<NSOutlineViewDelegate>)
+@interface wxCocoaOutlineView : NSOutlineView <NSOutlineViewDelegate>
 {
 @private
     // column and row of the cell being edited or -1 if none