[#147552449] upgrade Ruby to 2.3 (#12)

- bump rails
- bump some gems
- add pessimistic version constraints to Gemfile
- add /coverage to .gitignore

.gitignore

@@ -6,3 +6,4 @@
 config/instagram.yml
 config/flickr.yml
 .capistrano/metrics
+/coverage

.ruby-version

@@ -1 +1 @@
-ruby-2.1.2
+ruby-2.3.4

.travis.yml

@@ -1,7 +1,7 @@
 language: ruby
 bundler_args: --without development
 rvm:
-  - 2.1.2
+  - 2.3.4
 before_install:
   - curl -O https://download.elasticsearch.org/elasticsearch/elasticsearch/elasticsearch-1.7.2.deb && sudo dpkg -i elasticsearch-1.7.2.deb && true
   - 'echo ''script.disable_dynamic: false'' | sudo tee --append /etc/elasticsearch/elasticsearch.yml'

Gemfile

@@ -1,37 +1,43 @@
 source 'https://rubygems.org'
-gem 'rails', '4.1.8'
-
-gem 'rails-api'
-gem 'grape'
-gem 'thin'
-
-gem 'jbuilder'
-
-gem 'capistrano'
-gem 'capistrano-bundler'
-gem 'capistrano-sidekiq'
-
-gem "elasticsearch-persistence", require: 'elasticsearch/persistence/model'
-gem 'instagram'
-gem 'flickraw'
-gem 'sidekiq'
-gem 'mock_redis'
-gem 'sidekiq-unique-jobs'
-gem 'sidekiq-failures'
+gem 'rails', '4.2.8'
+
+# 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 'jbuilder', '~> 2.2.5'
+
+gem 'capistrano', '~> 3.3.5'
+gem 'capistrano-bundler', '~> 1.1.3'
+gem 'capistrano-sidekiq', '~> 0.4.0'
+
+gem "elasticsearch-persistence", '~> 0.1.6', require: 'elasticsearch/persistence/model'
+gem 'elasticsearch-api', '~> 1.0.6'
+gem 'elasticsearch-model', '~> 0.1.0'
+gem 'elasticsearch-transport', '~> 1.0.6'
+gem 'instagram', '~> 1.1.3'
+gem 'flickraw', '~> 0.9.8'
+gem 'sidekiq', '~> 3.3.0'
+gem 'mock_redis', '~> 0.14.0'
+gem 'sidekiq-unique-jobs', '~> 3.0.11'
+gem 'sidekiq-failures', '~> 0.4.3'
 gem 'sinatra', '>= 1.3.0', :require => nil
-gem 'whenever', :require => false
+gem 'whenever', '~> 0.9.4', :require => false
 
-gem 'newrelic_rpm'
-gem "airbrake"
+gem 'newrelic_rpm', '~> 4.2.0.334'
+gem "airbrake", '~> 4.1.0'
 
-gem 'feedjira'
+gem 'feedjira', '~> 1.5.0'
 
 group :development, :test do
   gem 'rspec-rails', '~> 3.0.0'
 end
 
 group :test do
-  gem 'rspec-sidekiq', github: 'yelled3/rspec-sidekiq', branch: 'rspec3-beta'
+  gem 'rspec-sidekiq', '~> 3.0.1'
   gem 'simplecov', '~> 0.7.1'
-  gem "codeclimate-test-reporter", require: nil
+  gem "codeclimate-test-reporter", '~> 0.4.3', require: nil
 end