Added missing UIView+WebCacheOperation of submodule SDWebImage

I use multiple submodules in a project which all includes the SDWebImage Library. I prefer to use the Library from the ShareKit Library. But when using a method like setImageUrl with placeholder from UIImageView+WebCache a crash happen because the new WebOperation class is not included in ShareKit so far. I think when including SDWebImage in ShareKit it should be included completely.
What do you think?