625: scanline subpix version 1, multi-states

see AADemo_Test3.cs
629: subpix scanline 1 not complete
629.1: subpix scanline 1
631: TypeFacePrinter member modifiers
632: fixed subpix render

still need adjust subpix blending function
633: test subpix, still not correct

need study more!
Merge branch 'v_subpixel_study' into v_fonts