chore(node): bump min node & npm versions

node: ^4.4.0
npm: ^2.14.20

[skip ci]

Author: Awk34

Diff for: app/templates/_package.json

@@ -165,8 +165,8 @@
     "tslint": "^3.5.0"<% } %>
   },
   "engines": {
-    "node": "^4.2.3",
-    "npm": "^2.14.7"
+    "node": "^4.4.0",
+    "npm": "^2.14.20"
   },
   "scripts": {
     "start": "node server",<% if(filters.gulp) { %>

Diff for: package.json

@@ -63,8 +63,8 @@
     "yeoman-test": "^1.1.0"
   },
   "engines": {
-    "node": "^4.2.3",
-    "npm": "^2.14.7"
+    "node": "^4.4.0",
+    "npm": "^2.14.20"
   },
   "license": "BSD-2-Clause"
 }