Added WRL frontend for Win8 and WP8

Merged Qt, SDL and WRL frontend on the same corewrapper
Moved OpenGL code out of SDL and Qt frontends to OpenGl backend
(JGfx.cpp)
Updated file system and network code to be compatible with WRL

JGE/include/Threading.h

@@ -1,7 +1,7 @@
 #ifndef THREADING_H
 #define THREADING_H
 
-#if !defined(PSP) && !defined(QT_CONFIG)
+#if !defined(PSP) && !defined(QT_CONFIG) && !defined(WP8)
 #include <boost/date_time.hpp>
 
 #ifdef WIN32
@@ -14,7 +14,7 @@
 #endif
 
 #include <boost/thread/mutex.hpp>
-#elif !defined(QT_CONFIG)
+#elif defined(PSP)
 #include <boost/bind.hpp>
 #include <boost/shared_ptr.hpp>
 
@@ -538,6 +538,80 @@ namespace boost
     }
 }
 
+#elif defined(WP8)
+
+#include <thread>
+#include <mutex>
+
+namespace boost
+{
+	typedef std::thread thread;
+
+    template <class Mutex>
+    struct unique_lock
+    {
+        unique_lock(Mutex& inMutex) : mMutex(&inMutex)
+        {
+            mMutex->lock();
+        }
+
+        ~unique_lock()
+        {
+            mMutex->unlock();
+        }
+
+        Mutex* mMutex;
+    };
+
+    class mutex 
+    {
+    public:
+
+        typedef unique_lock<mutex> scoped_lock;
+
+        mutex()
+          : mQMutex()
+        {
+        }
+
+        ~mutex()
+        {
+        }
+
+        void lock()
+        {
+            mQMutex.lock();
+        }
+
+        void unlock()
+        {
+            mQMutex.unlock();
+        }
+
+        std::mutex mQMutex;
+
+    private:
+        mutex(mutex const&);
+        mutex& operator=(mutex const&);
+    };
+
+    namespace posix_time
+    {
+        typedef unsigned int milliseconds;
+    }
+
+    /**
+    ** boost's platform neutral sleep call.
+    */
+    namespace this_thread
+    {
+        inline void sleep(boost::posix_time::milliseconds const& time)
+        {
+			std::this_thread::sleep_for(std::chrono::milliseconds(time));
+        }
+    }
+}
+
 #endif
 
 #endif // THREADING_H