Refactored the ReentrantMutex support so that it utilises the underling thread implementation for recusive mutex support.

src/OpenThreads/win32/Win32Mutex.cpp

@@ -81,7 +81,10 @@ static void _S_nsec_sleep(int __log_nsec) {
 //
 // Use: public.
 //
-Mutex::Mutex() {
+Mutex::Mutex(MutexType type):
+    _mutexType(type)
+)
+{
     Win32MutexPrivateData *pd = new Win32MutexPrivateData();
     _prvData = static_cast<void *>(pd);
 }