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/gdbengine.h

@@ -137,7 +137,7 @@ private:
     //
     // Own stuff
     //
-    void showDebuggingHelperWarning();
+
     int currentFrame() const;
     QString currentWorkingDirectory() const { return m_pwd; }
 
@@ -202,7 +202,6 @@ private:
     void handleTargetCore(const GdbResultRecord &response);
     void handleExit(const GdbResultRecord &response);
     void debugMessage(const QString &msg);
-    QString dumperLibraryName() const;
 
     OutputCollector m_outputCollector;
     QTextCodec *m_outputCodec;