Pass the env correctly for a .hooks script.

The environment was being passed as the arguments,
which doesn't work very well since it's an object.
Instead, pass empty arguments.

Author: reid

lib/utils/lifecycle.js

@@ -46,7 +46,7 @@ function lifecycle (pkg, stage, cb) {
     var hook = path.join(npm.dir, ".hooks", stage)
     fs.stat(hook, function (er) {
       if (er) return cb()
-      exec(hook, env, function (er) {
+      exec(hook, [], env, function (er) {
         if (er) log("Failed to exec "+stage+" hook script", pkg._id)
         if (npm.ROLLBACK) return cb()
         cb(er)