ignore *prepare.log files
add taffybar with dependencies

Closes #146.
Updates 2014-05-01

    attoparsec
    blaze-html
    conduit
    conduit-extra
    contravariant
    distributive
    ghc-mod
    largeword
    pandoc-types
    streaming-commons
    text
    warp

Signed-off-by: Magnus Therning <magnus@therning.org>