Updated dependencies

Author: oleersoy

package.json

@@ -24,8 +24,7 @@
     "url": "https://github.com/superfly-css/superfly-css-task-build/issues"
   },
   "homepage": "https://github.com/superfly-css/superfly-css-task-build#readme",
-  "devDependencies": {
-    "gulp": "^3.9.0",
+  "dependencies": {
     "gulp-postcss": "^6.0.1",
     "autoprefixer": "^6.1.0",
     "postcss-calc": "^5.0.0",