chore(test): use babel preset

Author: azu

.babelrc

@@ -1,3 +1,12 @@
 {
-    "presets": ["es2015"]
-}
+  "presets": [
+    "es2015"
+  ],
+  "env": {
+    "development": {
+      "presets": [
+        "power-assert"
+      ]
+    }
+  }
+}

package.json

@@ -39,11 +39,12 @@
   "devDependencies": {
     "babel-cli": "^6.3.13",
     "babel-preset-es2015": "^6.3.13",
+    "babel-preset-power-assert": "^1.0.0",
+    "babel-register": "^6.9.0",
     "codecov.io": "^0.1.6",
     "connect": "^3.4.0",
     "eslint": "^2.3.0",
     "eslint-plugin-markdown": "^1.0.0-beta",
-    "espower-babel": "^4.0.0",
     "gitbook-cli": "^2.1.2",
     "gitbook-plugin-edit-link": "^2.0.0",
     "gitbook-plugin-ga": "^1.0.0",
@@ -59,7 +60,7 @@
     "nlcst-to-string": "^1.0.0",
     "node-fetch": "^1.3.2",
     "npm-run-all": "^1.2.8",
-    "power-assert": "^1.0.0",
+    "power-assert": "^1.4.1",
     "redux": "^3.5.2",
     "remark": "^4.1.1",
     "stemming-x-keywords": "^1.0.3",

test/mocha.opts

@@ -1,3 +1,3 @@
 --timeout 100000
 --recursive
---compilers js:espower-babel/guess
+--compilers js:babel-register