message: update curl so we don't need so may hacks
diff: @@ -21,16 +21,14 @@ atty = "0.2"
  crates-io = { path = "src/crates-io", version = "0.18" }
  crossbeam = "0.3"
  crypto-hash = "0.3.1"
  -curl = "0.4.12"
  +curl = "0.4.13"
  env_logger = "0.5.4"
  failure = "0.1.1"
  filetime = "0.2"
  flate2 = "1.0"
  fs2 = "0.4"
  -git2 = "0.7.2"
  +git2 = "0.7.3"
  git2-curl = "0.8.1"
  -libgit2-sys = "0.7.5" # required only for minimal-versions. brought in by git2 and git2-curl.
  -libssh2-sys = "0.2.8" # required only for minimal-versions. brought in by libgit2-sys.
  glob = "0.2.11"
  hex = "0.3"
  home = "0.3"
  @@ -40,6 +38,7 @@ jobserver = "0.1.11"
  lazycell = "1.0"
  libc = "0.2"
  log = "0.4"
  +libgit2-sys = "0.7.5"
  num_cpus = "1.0"
  rustfix = "0.4"
  same-file = "1"
  @@ -67,10 +66,6 @@ core-foundation = { version = "0.6.0", features = ["mac_os_10_7_support"] }
  [target.'cfg(windows)'.dependencies]
  miow = "0.3.1"
  -[target.'cfg(windows)'.dev-dependencies]
  -gcc = "0.3.23" # required only for minimal-versions on windows. brought in by flate2 and others.
  -cmake = "0.1.24" # required only for minimal-versions on windows. brought in as build-dependency on libgit2-sys.
  -
  [target.'cfg(windows)'.dependencies.winapi]
  version = "0.3"
  features = [
  