Debugger: Introduce "Close memory buffers on exit" option

The usual case is probably to want normal editors stay open,
but memory/diassembler removed, but all other combinations
may be useful at times. So use two options instead of one.

Change-Id: I58c3951cc507c7e66a8d7a65b459a036e6a5d801
Reviewed-by: Christian Stenger <christian.stenger@theqtcompany.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/debugger/debuggeractions.h

@@ -99,7 +99,8 @@ enum DebuggerActionCode
     LogTimeStamps,
     VerboseLog,
     OperateByInstruction,
-    CloseBuffersOnExit,
+    CloseSourceBuffersOnExit,
+    CloseMemoryBuffersOnExit,
     SwitchModeOnExit,
     BreakpointsFullPathByDefault,
     RaiseOnInterrupt,