Terminal: add finished signal

Change-Id: I9d560d1f1bbaa94ae75420002744073a1e8fad1a
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

src/plugins/terminal/terminalwidget.h

@@ -50,6 +50,7 @@ public:
 
 signals:
     void started(qint64 pid);
+    void finised(int exitCode);
     void cwdChanged(const Utils::FilePath &cwd);
     void commandChanged(const Utils::CommandLine &cmd);
     void titleChanged();