Moved error listener to Redis adapter init

Calling .on('error') repeatedly from Web middlewares was causing warnings and a memory leak in the long run.
Removed setMaxListeners(0)

Since the warning should no longer be produced, the warning suppression should not be present in the source so that further memory leaks may be found promptly.
Merge pull request #2 from rkaw92/patch-1

Fix Redis error handler set-up