Start on dumper support for CDB, bug fixes.

Make command execution output shown, use Wide version
of Debug Callbacks and output, provide bases classes
for other output and event handlers, move common
dumper functionality into debugger manager.

src/plugins/debugger/cdb/cdbdebugoutput.cpp

@@ -155,5 +155,18 @@ void CdbDebugOutput::output(ULONG mask, const QString &msg)
     }
 }
 
+// Utility class to temporarily redirect output to another handler
+// as long as in scope
+OutputRedirector::OutputRedirector(IDebugClient5 *client, IDebugOutputCallbacksWide *newHandler) :
+        m_client(client),
+        m_oldHandler(CdbDebugOutputBase::getOutputCallback(client))
+{
+    m_client->SetOutputCallbacksWide(newHandler);
+}
+OutputRedirector::~OutputRedirector()
+{
+    m_client->SetOutputCallbacksWide(m_oldHandler);
+}
+
 } // namespace Internal
 } // namespace Debugger