🐛 bug(npm): fix installing bug

Closes #46

package.json

@@ -85,11 +85,11 @@
     "dev": "webpack-dev-server --quiet --config config/webpack.test.conf.js",
     "docs": "gitbook serve ./gitbook ./docs",
     "docs:build": "gitbook build ./gitbook ./docs",
+    "docs:install": "gitbook install ./gitbook",
     "e2e": "webpack-dev-server --quiet --config config/webpack.e2e.conf.js & mocha --opts test/e2e/mocha.opts --harmony test/e2e/test.js && kill $! || (kill $! && exit 1)",
     "ie": "VUE_I18N_TYPE=sauce SAUCE=batch2 karma start config/karma.conf.js",
     "lint": "eslint src/*.js test/**/*.js config/*.js",
     "mobile": "VUE_I18N_TYPE=sauce SAUCE=batch3 karma start config/karma.conf.js",
-    "postinstall": "gitbook install ./gitbook",
     "proto": "webpack-dev-server --quite --config config/webpack.dev.conf.js --host 0.0.0.0",
     "release": "conventional-github-releaser -n ./node_modules/git-commit-message-convention/convention.js",
     "sauce": "npm run coolkids && npm run ie && npm run mobile",