Make sure clippy does not duplicate depenencies

Author: oli-obk

src/Cargo.lock

@@ -310,17 +310,20 @@ name = "clippy"
 version = "0.0.211"
 dependencies = [
  "ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "backtrace 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "cargo_metadata 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "clippy-mini-macro-test 0.2.0",
  "clippy_lints 0.0.211",
  "compiletest_rs 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "derive-new 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_version 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
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