Editor code: tidy up BOOLs,NULLs and overrides pt6.

A few 'typedefs' replaced by 'using's
This shouldn't have any functional changes at all, just c++17 modernization
It's a part 6 of a split #2847

Signed-off-by: Nemerle <nemerle5+git@gmail.com>

Code/Editor/SelectEAXPresetDlg.cpp

@@ -49,7 +49,7 @@ QString CSelectEAXPresetDlg::GetCurrPreset() const
     {
         return m_ui->listView->currentIndex().data().toString();
     }
-    // EXCEPTION: OCX Property Pages should return FALSE
+    // EXCEPTION: OCX Property Pages should return false
     return QString();
 }