Bump HTTPClient SHA1

The data field in the Response object is now an IOBuffer (previously was a String)
Bump AWS SHA1

Changes due to HTTPClient.jl now returning an IOBuffer.
bump PyPlot
Updated MCMC (summary statistics)
Merge pull request #392 from scidom/MCMC

Update MCMC (summary stats)
GZip: fix deprecated use of contains()
Merge pull request #394 from nlhepler/devel

GZip: fix deprecated use of contains()
NumericExtensions v0.2.14
Bump Homebrew
Distributions v0.2.9
Bump AWS SHA1
Add missing Iterators dependency for Compose
Bump ZMQ for Win 32&64 binaries

fixes https://github.com/JuliaLang/ZMQ.jl/issues/30