Package grunt (#22396)

Remove docs files and Gruntfile from package managers

bower.json

@@ -25,6 +25,7 @@
     "composer.json",
     "CONTRIBUTING.md",
     "docs",
+    "Gruntfile.js",
     "js/tests",
     "test-infra"
   ],

package.json

@@ -88,10 +88,8 @@
   },
   "files": [
     "dist",
-    "grunt",
     "js/**/*.js",
     "scss/**/*.scss",
-    "Gruntfile.js",
     "LICENSE"
   ],
   "jspm": {