Added option (#define CAPTURE_STDERR)

if set then the DebugTrace calls only for failing tests are shown

JGE/include/OutputCapturer.h

@@ -0,0 +1,28 @@
+#ifndef OUTPUTCAPTURER_H
+#define OUTPUTCAPTURER_H
+
+#if defined(QT_CONFIG)
+#include <Qt>
+#include <string>
+#include <sstream>
+
+class OutputCapturer
+{
+private:
+    static std::ostringstream stream;
+public:
+    static void add(const std::string& s) {
+        stream << s << "\n";
+    }
+    static void debugAndClear() {
+        stream.flush();
+        qDebug("%s", stream.str().c_str());
+        stream.str("");
+    }
+    static void clear() {
+        stream.str("");
+    }
+};
+#endif
+
+#endif // OUTPUTCAPTURER_H