[fix] Update path to require statement in Redis store

lib/nconf/stores/redis.js

@@ -8,7 +8,7 @@
 var async = require('async'),
     redis = require('redis'),
     nconf = require('nconf'),
-    Memory = require('./Memory').Memory;
+    Memory = require('./memory').Memory;
 
 //
 // ### function Redis (options)