Merge branch 'redis_config_consistency' into 'master'

Redis configuration consistency

Related https://gitlab.com/gitlab-org/gitlab-ce/commit/cf669551f69edd66913d22c96cf1de1302e7990e

See merge request !3697

config/initializers/session_store.rb

@@ -14,7 +14,7 @@ if Rails.env.test?
   Gitlab::Application.config.session_store :cookie_store, key: "_gitlab_session"
 else
   redis_config = Gitlab::Redis.redis_store_options
-  redis_config[:namespace] = 'session:gitlab'
+  redis_config[:namespace] = Gitlab::Redis::SESSION_NAMESPACE
   
   Gitlab::Application.config.session_store(
     :redis_store, # Using the cookie_store would enable session replay attacks.

config/initializers/sidekiq.rb

-SIDEKIQ_REDIS_NAMESPACE = 'resque:gitlab'
-
 Sidekiq.configure_server do |config|
   config.redis = {
     url: Gitlab::Redis.url,
-    namespace: SIDEKIQ_REDIS_NAMESPACE
+    namespace: Gitlab::Redis::SIDEKIQ_NAMESPACE
   }
 
   config.server_middleware do |chain|
@@ -30,6 +28,6 @@ end
 Sidekiq.configure_client do |config|
   config.redis = {
     url: Gitlab::Redis.url,
-    namespace: SIDEKIQ_REDIS_NAMESPACE
+    namespace: Gitlab::Redis::SIDEKIQ_NAMESPACE
   }
 end

lib/gitlab/redis.rb

 module Gitlab
   class Redis
     CACHE_NAMESPACE = 'cache:gitlab'
+    SESSION_NAMESPACE = 'session:gitlab'
+    SIDEKIQ_NAMESPACE = 'resque:gitlab'
 
     attr_reader :url