[npm] Revert update of deps to support Node v0.12

Bug:

  Upgrading the dependencies 'file-type' and 'babel-eslint'
  removed support for Node.js v0.12 series.

  We are intending to continue to support 0.12 until we
  reach v1.

package.json

@@ -29,7 +29,7 @@
     "debug": "^2.2.0",
     "depd": "^1.1.0",
     "eventemitter3": "^2.0.2",
-    "file-type": "^4.0.0",
+    "file-type": "^3.9.0",
     "mime": "^1.3.4",
     "pump": "^1.0.1",
     "request": "^2.69.0",
@@ -37,7 +37,7 @@
   },
   "devDependencies": {
     "babel-cli": "^6.6.5",
-    "babel-eslint": "^7.1.1",
+    "babel-eslint": "^6.1.2",
     "babel-plugin-transform-class-properties": "^6.6.0",
     "babel-plugin-transform-es2015-destructuring": "^6.6.5",
     "babel-plugin-transform-es2015-parameters": "^6.7.0",