Update grunt-gitbook

Author: SamyPesse

package.json

@@ -11,7 +11,7 @@
     "dependencies": {},
     "devDependencies": {
         "grunt": "~0.4.1",
-        "grunt-gitbook": "git+https://github.com/GitbookIO/grunt-gitbook.git",
+        "grunt-gitbook": "0.0.1",
         "grunt-gh-pages": "0.9.1",
         "grunt-contrib-clean": "~0.5.0"
     },