[enh] fix diff augmented list algorithm for line proxy to take blank line into account
[enh] yay, insert blank lines in line proxy (finallygit add -p)
[mod] update TODO
[enh] test append
[enh] test pop for line proxy
[enh] test __del__ for line proxy
[enh] test remove for line proxy
[enh] test __setslice__ for line proxy
[enh] test __delslice__ for line proxy
[enh] test __getslice__ for line proxy
[enh] test extend for line proxy
[enh] test different indentation for line proxy
[enh] test that the next block indentation isnt break for line proxy
[mod] update TODO