clean up dependencies

package.json

@@ -32,18 +32,15 @@
     "cross-spawn": "4.0.2",
     "del": "2.2.2",
     "glob-promise": "1.0.6",
-    "gulp-benchmark": "^1.1.1",
     "htmlescape": "1.1.1",
     "loader-utils": "0.2.16",
     "minimist": "1.2.0",
-    "mkdirp-then": "1.2.0",
     "mz": "2.4.0",
     "path-match": "1.2.4",
     "react": "15.3.2",
     "react-dom": "15.3.2",
     "react-hot-loader": "3.0.0-beta.6",
     "resolve": "1.1.7",
-    "run-sequence": "1.2.2",
     "send": "0.14.1",
     "url": "0.11.0",
     "webpack": "1.13.2",
@@ -56,9 +53,11 @@
     "gulp": "3.9.1",
     "gulp-ava": "0.14.1",
     "gulp-babel": "6.1.2",
+    "gulp-benchmark": "^1.1.1",
     "gulp-cached": "1.1.0",
     "gulp-notify": "2.2.0",
     "husky": "^0.11.9",
+    "run-sequence": "1.2.2",
     "standard": "^8.4.0",
     "webpack-stream": "3.2.0"
   },