Add test for installing starter using 'gatsby new'

test/integration/install-starter.js

@@ -0,0 +1,14 @@
+import test from 'ava'
+import fs from 'fs-extra'
+import Promise from 'bluebird'
+const remove = Promise.promisify(fs.remove)
+const tmpdir = require('os').tmpdir()
+
+import { gatsby } from '../support'
+
+test('calling gatsby new succesfully creates new site from default starter', async t => {
+  await remove(`${tmpdir}/gatsby-default-starter`)
+  const noArgs = await gatsby(['new', `${tmpdir}/tmp/gatsby-default-starter`])
+  console.log(noArgs)
+  t.is(noArgs.code, 0)
+})