Bump redis-namespace to 1.6.0

This reflects the version used in CE.

Full list of changes:
https://github.com/resque/redis-namespace/blob/master/CHANGELOG.md

Gemfile.lock

@@ -5,7 +5,8 @@ PATH
       connection_pool (~> 2.2.1)
       pg (~> 0.18.4)
       quantile (~> 0.2.0)
-      redis-namespace (~> 1.5.2)
+      redis (~> 3.2)
+      redis-namespace (~> 1.6.0)
       sidekiq (~> 5.2.1)
       sinatra (~> 1.4.7)
 
@@ -25,8 +26,8 @@ GEM
       rack
     rainbow (2.1.0)
     redis (3.3.5)
-    redis-namespace (1.5.3)
-      redis (~> 3.0, >= 3.0.4)
+    redis-namespace (1.6.0)
+      redis (>= 3.0.4)
     rspec (3.7.0)
       rspec-core (~> 3.7.0)
       rspec-expectations (~> 3.7.0)

gitlab-monitor.gemspec

@@ -24,7 +24,8 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency "sinatra", "~> 1.4.7"
   s.add_runtime_dependency "quantile", "~> 0.2.0"
   s.add_runtime_dependency "sidekiq", "~> 5.2.1"
-  s.add_runtime_dependency "redis-namespace", "~> 1.5.2"
+  s.add_runtime_dependency "redis", "~> 3.2"
+  s.add_runtime_dependency "redis-namespace", "~> 1.6.0"
   s.add_runtime_dependency "connection_pool", "~> 2.2.1"
 
   s.add_development_dependency "rspec", "~> 3.7.0"