Move ChromeTracing in its own file, and add tracing support for VR server (App_SharedMemoryPhysics_VR)

Add a bit of extra sleep in PhysicsServer thread, to make rendering smoother.

examples/Utils/ChromeTraceUtil.h

@@ -0,0 +1,9 @@
+
+#ifndef B3_CHROME_TRACE_UTIL_H
+#define B3_CHROME_TRACE_UTIL_H
+
+void b3ChromeUtilsStartTimings();
+void b3ChromeUtilsStopTimingsAndWriteJsonFile();
+void b3ChromeUtilsEnableProfiling();
+
+#endif//B3_CHROME_TRACE_UTIL_H