add some preinstall/postinstall scripts

package.json

@@ -13,6 +13,8 @@
     "telebitd": "bin/telebitd.js"
   },
   "scripts": {
+    "preinstall": "node scripts/preinstall.js",
+    "postinstall": "node scripts/postinstall.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "repository": {