MLineStencil [Xpos.w,Ypos.w,]Xpos2.w,Ypos2.w[,Colour.b];Draw a line from X1,Y1 to X2,Y2 in a stencil, Col or 0

Does the same as MLine, except that the line is drawn to the stencil of the
currently used chunky Bitmap, and the colour drawn will /represent/ the
specified colour or ink.