Add wxNOEXCEPT and use it for std::streambuf-derived classes.

This fixes warnings from Intel compiler about overriding function using a
different exception specification than the base one and also incidentally
provides a handy macro that can be useful in other situations.

Closes #14826.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72978 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/textctrl.h

@@ -679,7 +679,7 @@ public:
     // --------
 
     wxTextCtrlBase() { }
-    virtual ~wxTextCtrlBase() { }
+    virtual ~wxTextCtrlBase() wxNOEXCEPT { }
 
 
     // more readable flag testing methods