CVS: Modernize

* Use pragma once
* Use some more overrides
* Tiny clean-ups here and there

Change-Id: I951afa8ed31c5f414d4ae872c79f80db19909ee0
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/cvs/cvseditor.h

@@ -23,8 +23,7 @@
 **
 ****************************************************************************/
 
-#ifndef CVSEDITOR_H
-#define CVSEDITOR_H
+#pragma once
 
 #include <vcsbase/vcsbaseeditor.h>
 
@@ -54,5 +53,3 @@ private:
 
 } // namespace Internal
 } // namespace Cvs
-
-#endif // CVSEDITOR_H