Update dev-dependencies

Author: wooorm

package.json

@@ -24,15 +24,15 @@
     "nlcst-to-string": "^2.0.0"
   },
   "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",
     "retext": "^5.0.0",
     "tape": "^4.6.2",
     "unist-util-visit": "^1.0.0",
-    "xo": "^0.18.2"
+    "xo": "^0.20.0"
   },
   "scripts": {
     "build-md": "remark . --quiet --frail --output",
@@ -54,6 +54,9 @@
     "space": true,
     "esnext": false,
     "rules": {
+      "guard-for-in": "off",
+      "no-var": "off",
+      "prefer-arrow-callback": "off",
       "unicorn/prefer-type-error": "off"
     },
     "ignore": [

test.js

@@ -4,7 +4,7 @@ var assert = require('assert');
 var test = require('tape');
 var visit = require('unist-util-visit');
 var retext = require('retext');
-var isLiteral = require('./');
+var isLiteral = require('.');
 
 test('isLiteral()', function (t) {
   t.throws(