MxSemphore + MxThread + MxThread implementions (#80)

* Add MxSemphore + MxThread and the two implementations I could find
  of MxThread (consumers extend it and override the Run method).

* Implement a function in MxDiskStreamProvider which uses thread and
  semaphore to confirm correct layout / size of those classes.

* All 100% match except two functions with a pair of registers swapped.

LEGO1/mxsemaphore.cpp

@@ -0,0 +1,29 @@
+
+#include "mxsemaphore.h"
+
+// OFFSET: LEGO1 0x100c87d0
+MxSemaphore::MxSemaphore()
+{
+  m_hSemaphore = NULL;
+}
+
+// OFFSET: LEGO1 0x100c8800
+MxResult MxSemaphore::Init(MxU32 p_initialCount, MxU32 p_maxCount)
+{
+  MxResult result = FAILURE;
+  if (m_hSemaphore = CreateSemaphoreA(NULL, p_initialCount, p_maxCount, NULL))
+    result = SUCCESS;
+  return result;
+}
+
+// OFFSET: LEGO1 0x100c8830
+void MxSemaphore::Wait(MxU32 p_timeoutMS)
+{
+  WaitForSingleObject(m_hSemaphore, p_timeoutMS);
+}
+
+// OFFSET: LEGO1 0x100c8850
+void MxSemaphore::Release(MxU32 p_releaseCount)
+{
+  ReleaseSemaphore(m_hSemaphore, p_releaseCount, NULL);
+}