MSBlock [ShapeNumber.w,]Xpos.w,Ypos.w ; Block-blit shape to bitmap & cookie 2 stencil, Xpos&Width in 16's

Performs a straight unmasked-blit of a chunky Shape into the chunky Bitmap to
coordinates Xpos,Ypos. Xpos should be a multiple of 16 and the shape should also
have a Width that is multiple of 16. The blit will be an un-masked blit and will
not be affected by MSBlitMode but it is possible to cut-blit the block-type Shape
`behind' the Bitmap's stencil using MSBlitCut On. Normally the Shape's cookie will
also be block-blitted to the Bitmap's stencil.