Upgrade from rails 4 to rails 5 (#6)

Gemfile

@@ -1,14 +1,19 @@
 source 'https://rubygems.org'
-gem 'rails', '4.2.10'
+
+git_source(:github) do |repo_name|
+  repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include?("/")
+  "https://github.com/#{repo_name}.git"
+end
+
+gem 'rails', '5.1.4'
 
 # Temporarily limiting rake version:
 # #http://stackoverflow.com/questions/35893584/nomethoderror-undefined-method-last-comment-after-upgrading-to-rake-11
 gem 'rake', '~> 10.0'
 
-gem 'grape', '~> 0.9.0'
-gem 'thin', '~> 1.6.3'
+gem 'grape', '~> 1.0.0'
 
-gem 'jbuilder', '~> 2.2.5'
+gem 'jbuilder', '~> 2.6.4'
 
 gem 'capistrano', '~> 3.3.5'
 gem 'capistrano-bundler', '~> 1.1.3'
@@ -18,25 +23,37 @@ gem "elasticsearch-persistence", '~> 5.0', require: 'elasticsearch/persistence/m
 gem 'elasticsearch-api', '~> 6.0'
 gem 'elasticsearch-model', '~> 5.0'
 gem 'elasticsearch-transport', '~> 6.0'
-gem 'hashie', '~> 3.3.2' # Hashie::[email protected] will emit warning on key collision. Lock to 3.3.2 to avoid code change.
-gem 'instagram', '~> 1.1.3'
+gem 'hashie', '~> 3.5.7'
+gem 'instagram-continued', '~> 1.4.0'
 gem 'flickraw', '~> 0.9.8'
-gem 'sidekiq', '~> 3.3.0'
-gem 'mock_redis', '~> 0.14.0'
+gem 'sidekiq', '< 6'
+gem 'redis-namespace', '~> 1.6.0' # use redis database index instead?
+gem 'mock_redis', '~> 0.17.3'
 gem 'sidekiq-unique-jobs', '3.0.11' # sidekiq-unique-jobs > 3.0.11 broke spec
-gem 'sidekiq-failures', '~> 0.4.3'
-gem 'sinatra', '>= 1.3.0', :require => nil
+gem 'sidekiq-failures', '~> 1.0.0'
+gem 'sinatra', '>= 2.0', :require => nil
 gem 'whenever', '~> 0.9.4', :require => false
 
 gem 'newrelic_rpm', '~> 4.2.0.334'
-gem "airbrake", '~> 4.1.0'
+gem 'airbrake', '~> 7.1.1'
 
-gem 'feedjira', '~> 1.5.0'
+gem 'feedjira', '~> 2.1.1'
 
 group :development, :test do
+  gem 'puma', '~> 3.11'
+
   gem 'binding_of_caller'
   gem 'pry-rails'
-  gem 'rspec-rails', '~> 3.0.0'
+  gem 'rspec-rails', '~> 3.7.2'
+end
+
+group :development do
+  # Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
+  gem 'web-console', '>= 3.3.0'
+  gem 'listen', '>= 3.0.5', '< 3.2'
+  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
+  gem 'spring'
+  gem 'spring-watcher-listen', '~> 2.0.0'
 end
 
 group :test do