Adding gulp-cli to packages.

package.json

@@ -6,6 +6,7 @@
     "del": "^2.2.2",
     "front-matter": "^2.1.2",
     "gulp": "^3.9.1",
+    "gulp-cli": "^1.2.2",
     "gulp-cssnano": "^2.1.2",
     "gulp-plumber": "^1.1.0",
     "gulp-print": "^2.0.1",