Pin dependencies (#3)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

Author: renovate[bot]

package.json

@@ -28,18 +28,18 @@
     "@aureooms/js-pairing-heap": "^0.1.1"
   },
   "devDependencies": {
-    "ava": "^0.25.0",
-    "babel-cli": "^6.26.0",
-    "babel-polyfill": "^6.26.0",
-    "babel-preset-env": "^1.6.1",
-    "codeclimate-test-reporter": "^0.5.0",
-    "coveralls": "^3.0.0",
-    "esdoc": "^1.0.4",
-    "esdoc-inject-script-plugin": "^1.0.0",
-    "esdoc-inject-style-plugin": "^1.0.0",
-    "esdoc-standard-plugin": "^1.0.0",
-    "np": "^2.20.0",
-    "nyc": "^11.4.1"
+    "ava": "0.25.0",
+    "babel-cli": "6.26.0",
+    "babel-polyfill": "6.26.0",
+    "babel-preset-env": "1.7.0",
+    "codeclimate-test-reporter": "0.5.1",
+    "coveralls": "3.0.9",
+    "esdoc": "1.1.0",
+    "esdoc-inject-script-plugin": "1.0.0",
+    "esdoc-inject-style-plugin": "1.0.0",
+    "esdoc-standard-plugin": "1.0.0",
+    "np": "2.20.1",
+    "nyc": "11.9.0"
   },
   "homepage": "https://aureooms.github.io/js-mincut",
   "keywords": [