Update dependencies to enable Greenkeeper 🌴 (#164)

* chore(package): update dependencies

https://greenkeeper.io/

* Update to eslint-config-airbnb-base v11.0.1

This includes updated peerDependencies

* Update to ESLint v3.13.0

Satisfies the peerDependencies of `eslint-config-airbnb-base@^11.0.1`.
Also simplifies the configuration a tad.

Author: greenkeeper[bot]

package.json

@@ -37,17 +37,16 @@
   },
   "devDependencies": {
     "coffeelint": "^1.14.2",
-    "eslint": "^3.7.1",
-    "eslint-config-airbnb-base": "^8.0.0",
-    "eslint-plugin-import": "^1.16.0"
+    "eslint": "^3.13.0",
+    "eslint-config-airbnb-base": "^11.0.1",
+    "eslint-plugin-import": "^2.2.0"
   },
   "eslintConfig": {
     "extends": "airbnb-base",
     "globals": {
       "atom": true
     },
     "env": {
-      "es6": true,
       "node": true
     }
   }