remove pre-commit package

package.json

@@ -169,7 +169,6 @@
     "koa-webpack-hot-middleware": "^1.0.3",
     "mocha": "^2.4.5",
     "node-watch": "^0.5.5",
-    "pre-commit": "^1.2.2",
     "prettier": "1.8.2",
     "react-addons-perf": "15.4.2",
     "react-addons-test-utils": "15.4.2",

yarn.lock

@@ -5720,10 +5720,6 @@ os-locale@^2.0.0:
     lcid "^1.0.0"
     mem "^1.1.0"
 
-os-shim@^0.1.2:
-  version "0.1.3"
-  resolved "https://registry.yarnpkg.com/os-shim/-/os-shim-0.1.3.tgz#6b62c3791cf7909ea35ed46e17658bb417cb3917"
-
 os-tmpdir@^1.0.0, os-tmpdir@^1.0.1, os-tmpdir@~1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/os-tmpdir/-/os-tmpdir-1.0.2.tgz#bbe67406c79aa85c5cfec766fe5734555dfa1274"
@@ -6198,14 +6194,6 @@ postinstall-build@^5.0.1:
   version "5.0.1"
   resolved "https://registry.yarnpkg.com/postinstall-build/-/postinstall-build-5.0.1.tgz#b917a9079b26178d9a24af5a5cd8cb4a991d11b9"
 
-pre-commit@^1.2.2:
-  version "1.2.2"
-  resolved "https://registry.yarnpkg.com/pre-commit/-/pre-commit-1.2.2.tgz#dbcee0ee9de7235e57f79c56d7ce94641a69eec6"
-  dependencies:
-    cross-spawn "^5.0.1"
-    spawn-sync "^1.0.15"
-    which "1.2.x"
-
 prelude-ls@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/prelude-ls/-/prelude-ls-1.1.2.tgz#21932a549f5e52ffd9a827f570e04be62a97da54"
@@ -7377,13 +7365,6 @@ sparkles@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/sparkles/-/sparkles-1.0.0.tgz#1acbbfb592436d10bbe8f785b7cc6f82815012c3"
 
-spawn-sync@^1.0.15:
-  version "1.0.15"
-  resolved "https://registry.yarnpkg.com/spawn-sync/-/spawn-sync-1.0.15.tgz#b00799557eb7fb0c8376c29d44e8a1ea67e57476"
-  dependencies:
-    concat-stream "^1.4.7"
-    os-shim "^0.1.2"
-
 spdx-correct@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/spdx-correct/-/spdx-correct-1.0.2.tgz#4b3073d933ff51f3912f03ac5519498a4150db40"
@@ -8284,7 +8265,7 @@ which-module@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/which-module/-/which-module-2.0.0.tgz#d9ef07dce77b9902b8a3a8fa4b31c3e3f7e6e87a"
 
-which@1, which@1.2.x, which@^1.2.12, which@^1.2.9:
+which@1, which@^1.2.12, which@^1.2.9:
   version "1.2.14"
   resolved "https://registry.yarnpkg.com/which/-/which-1.2.14.tgz#9a87c4378f03e827cecaf1acdf56c736c01c14e5"
   dependencies: