Grayscale example for C++ 5.0 and later

This example converts the bitmap to 12-bit grayscale.

ILEADRasterProcess *pRasterProc=NULL;
CoCreateInstance(CLSID_LEADRasterProcess, NULL, CLSCTX_ALL,
                 IID_ILEADRasterProcess, (void**)&pRasterProc);
pRasterProc->Grayscale(m_LEADRasterView1.GetRaster(), 12); //grayscale to 12-bit
pRasterProc->Release();