Build: Update to fixturify 3.0, and grunt-contrib-connect 4.0

* https://github.com/gruntjs/grunt-contrib-connect/blob/v4.0.0/CHANGELOG
* https://github.com/joliss/node-fixturify/blob/v3.0.0/CHANGELOG.md

Deprecation fixes, dep updates, minor size reduction.

Author: Krinkle

package-lock.json

@@ -66,10 +66,10 @@
     "eslint-plugin-n": "^15.0.0",
     "eslint-plugin-promise": "^6.2.0",
     "eslint-plugin-qunit": "^8.1.1",
-    "fixturify": "^2.1.1",
+    "fixturify": "^3.0.0",
     "fuzzysort": "1.2.1",
     "grunt": "^1.6.1",
-    "grunt-contrib-connect": "^3.0.0",
+    "grunt-contrib-connect": "^4.0.0",
     "grunt-contrib-copy": "^1.0.0",
     "grunt-contrib-qunit": "^8.0.1",
     "grunt-search": "^0.1.8",