Update dev-dependencies

Author: wooorm

package.json

@@ -22,13 +22,13 @@
   ],
   "dependencies": {},
   "devDependencies": {
-    "browserify": "^14.0.0",
+    "browserify": "^16.0.0",
     "esmangle": "^1.0.0",
     "nyc": "^11.0.0",
-    "remark-cli": "^4.0.0",
-    "remark-preset-wooorm": "^3.0.0",
+    "remark-cli": "^5.0.0",
+    "remark-preset-wooorm": "^4.0.0",
     "tape": "^4.4.0",
-    "xo": "^0.18.2"
+    "xo": "^0.20.0"
   },
   "scripts": {
     "build-md": "remark . -qfo",
@@ -49,6 +49,11 @@
   "xo": {
     "space": true,
     "esnext": false,
+    "rules": {
+      "guard-for-in": "off",
+      "no-var": "off",
+      "prefer-arrow-callback": "off"
+    },
     "ignores": [
       "unist-util-position.js"
     ]

test.js

@@ -1,7 +1,7 @@
 'use strict';
 
 var test = require('tape');
-var position = require('./index.js');
+var position = require('.');
 
 var properties = {
   position: {