Add Sidekiq 6 support

Author: scottbartell

.travis.yml

@@ -8,6 +8,12 @@ rvm:
 gemfile:
   - 'gemfiles/sidekiq_4.gemfile'
   - 'gemfiles/sidekiq_5.gemfile'
+  - 'gemfiles/sidekiq_6.gemfile'
+
+matrix:
+  exclude:
+    - rvm: 2.4.4
+      gemfile: gemfiles/sidekiq_6.gemfile
 
 deploy:
   provider: rubygems

gemfiles/sidekiq_6.gemfile

@@ -0,0 +1,5 @@
+source "https://rubygems.org"
+
+gem 'sidekiq', '~> 6.0'
+
+gemspec path: '../'

sidekiq-rate-limiter.gemspec

@@ -26,6 +26,6 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rspec", '~> 3.4'
   s.add_development_dependency "coveralls", '~> 0.8'
 
-  s.add_dependency "sidekiq", ">= 4.0", "< 6.0"
+  s.add_dependency "sidekiq", ">= 4.0", "< 7.0"
   s.add_dependency "redis_rate_limiter"
 end