update
git-annex.cabal: add missing http-client depend to S3

With the following flags:
  $ cabal configure --ghc --prefix=/usr --with-compiler=/usr/bin/ghc --with-hc-pkg=/usr/bin/ghc-pkg --prefix=/usr --libdir=/usr/lib64 --libsubdir=git-annex-5.20141203/ghc-7.8.3.20141119 --datadir=/usr/share/ --datasubdir=git-annex-5.20141203/ghc-7.8.3.20141119 --ghc-option=-O2 --ghc-option=+RTS --ghc-option=-H64M --ghc-option=-M4G --ghc-option=-RTS --ghc-option=-O0 --ghc-option=-j4 --ghc-option=-optl-Wl,-O1 --ghc-option=-optl-Wl,--as-needed --ghc-option=-optl-Wl,--hash-style=gnu --disable-executable-stripping --docdir=/usr/share/doc/git-annex-5.20141203 --verbose --sysconfdir=/etc --disable-library-stripping --flags=-android --flags=-androidsplice --flags=-assistant --flags=cryptohash --flags=dbus --flags=-desktop-notify --flags=dns --flags=-ekg --flags=-feed --flags=-inotify --flags=pairing --flags=production --flags=-quvi --flags=s3 --flags=tahoe --flags=tdfa --flags=-testsuite --flags=-webapp --flags=-webapp-secure --flags=-webdav --flags=-xmpp

ghc detects missing module (used directly by Remote.S3):
  Remote/Helper/Http.hs:16:8:
    Could not find module ‘Network.HTTP.Client’
    It is a member of the hidden package ‘http-client-0.3.8.2’.
    Perhaps you need to add ‘http-client’ to the build-depends in your .cabal file.
    Use -v to see a list of the files searched for.

Signed-off-by: Sergei Trofimovich <siarheit@google.com>
Merge branch 'master' of ssh://git-annex.branchable.com