Rename 'Standard Gaming Platform' to 'sgp' (#246)

* rename 'Standard Gaming Platform' to 'sgp'

* Adapt CMakeLists.txt files to renamed SGP directory

* Lowercase it

sgp/debug_util.cpp

@@ -0,0 +1,37 @@
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "debug_util.h"
+
+const void *const *StackTrace::Addresses(size_t* count) {
+  *count = trace_.size();
+  if (trace_.size())
+    return &trace_[0];
+  return NULL;
+}
+
+void sgp::dumpStackTrace(vfs::String const& msg)
+{
+	// the first error is the important one anyway
+	static bool already_dumping = false;
+
+	if(!already_dumping) // needs a mutes to be sure
+	{
+		already_dumping = true;
+		StackTrace str;
+		str.PrintBacktrace(msg.utf8().c_str());
+		already_dumping = false;
+	}
+}
+
+#ifdef __MINGW32__
+StackTrace::StackTrace()
+{
+}
+
+void StackTrace::PrintBacktrace(const char* msg)
+{
+}
+
+#endif