Update eslint dependencies and fix some linting errors

Author: marco-c

.eslintrc

@@ -15,6 +15,8 @@
     "no-param-reassign": 0,
     "quote-props": 0,
     "wrap-iife": [2, "inside"],
-    "import/no-unresolved": 0
+    "import/no-unresolved": 0,
+    "indent": 0,
+    "no-buffer-constructor": 0, // We still support Node v4.
   }
 }