cosine-Lanczos is missing the cosine taper

[water-e]

What we have been describing as a cosine-Lanczos filter is incorrectly labeled. It is a Lanczos filter, which is the composition of a truncated sinc function and a Lanczos windowing function (thought technically it isn't acting as a window here, it is part of the definition of a Lanczos filter. The cosine taper needs to be added.