update fastboot to 3.1.0

Author: kiwiupover

packages/ember-cli-fastboot/package.json

@@ -33,7 +33,7 @@
     "ember-cli-lodash-subset": "2.0.1",
     "ember-cli-preprocess-registry": "^3.1.2",
     "ember-cli-version-checker": "^3.0.0",
-    "fastboot": "^3.0.0",
+    "fastboot": "^3.1.0",
     "fastboot-express-middleware": "^2.0.0",
     "fastboot-transform": "^0.1.3",
     "fs-extra": "^7.0.0",