update deps, remove xtend (#3)

Author: joehand

.gitignore

@@ -25,3 +25,4 @@ build/Release
 # Dependency directory
 # https://www.npmjs.org/doc/misc/npm-faq.html#should-i-check-my-node_modules-folder-into-git
 node_modules
+package-lock.json

.travis.yml

@@ -1,7 +1,8 @@
 language: node_js
 node_js:
-  - '4'
-  - '6'
+  - 'lts/*'
+  - '8'
+  - 'node'
 cache:
   directories:
     - node_modules

index.js

@@ -1,12 +1,12 @@
 var stringKey = require('dat-encoding').toStr
 // var path = require('path')
-var xtend = require('xtend')
+var xtend = Object.assign
 var toiletdb = require('toiletdb')
 
 module.exports = function (archive, opts) {
   if (!opts) opts = {}
 
-  var db = toiletdb({name: '/dat.json', fs: archive})
+  var db = toiletdb({ name: '/dat.json', fs: archive })
   var fileDb = opts.file ? toiletdb(opts.file) : null
 
   var that = {