Add CheckSpelling support for OS X Cocoa, make sure NSTextView-based wxTextCtrls emit EVT_TEXT, and a fix for GetStyle when position == length.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62724 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/osx/cocoa/private.h

@@ -301,10 +301,12 @@ protected :
     @end
 
 
-    @interface wxNSTextView : NSTextView
+    @interface wxNSTextView : NSTextView <NSTextViewDelegate>
     {
     }
-
+    
+    - (void)textDidChange:(NSNotification *)aNotification;
+    
     @end
 
     @interface wxNSMenu : NSMenu

include/wx/osx/cocoa/private/textimpl.h

@@ -60,6 +60,8 @@ public:
     
     virtual bool GetStyle(long position, wxTextAttr& style);
     virtual void SetStyle(long start, long end, const wxTextAttr& style);
+    
+    virtual void CheckSpelling(bool check);
 
 protected:
     NSScrollView* m_scrollView;