Interpret unassigned hotkeys correctly.

* If a hotkey is set to "unassigned" (typically by causing a conflict), it 
  is not loaded correctly. The loader interprets "unassigned" as "keep the 
  default assignment", which leads to a conflict later that causes an 
  assertion failure.

common/hotkeys_basic.cpp

@@ -732,11 +732,7 @@ void ParseHotkeyConfig( const wxString&           data,
 
             if( hk_decr->m_InfoMsg == fctname )
             {
-                int code = KeyCodeFromKeyName( keyname );
-
-                if( code )
-                    hk_decr->m_KeyCode = code;
-
+                hk_decr->m_KeyCode = KeyCodeFromKeyName( keyname );
                 break;
             }
         }