Upgraded ruby to 2.2.4 and gems: sprockets-rails and bundler

.ruby-version

@@ -1 +1 @@
-2.2.3
+2.2.4

.travis.yml

@@ -1,6 +1,6 @@
 language: ruby
 rvm:
-  - "2.2.3"
+  - "2.2.4"
 before_script: rake db:setup
 before_script: bundle exec rake db:setup
 cache: bundler

Gemfile

@@ -3,7 +3,7 @@ source 'https://rubygems.org'
 #don't upgrade
 gem 'rails', '4.2.5'
 
-ruby '2.2.3'
+ruby '2.2.4'
 
 # Bundle edge Rails instead:
 # gem 'rails', github: 'rails/rails'

Gemfile.lock

@@ -287,10 +287,10 @@ GEM
     sprockets (3.5.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
-    sprockets-rails (2.3.3)
+    sprockets-rails (3.0.0)
-      actionpack (>= 3.0)
+      actionpack (>= 4.0)
-      activesupport (>= 3.0)
+      activesupport (>= 4.0)
-      sprockets (>= 2.8, < 4.0)
+      sprockets (>= 3.0.0)
     sqlite3 (1.3.11)
     temple (0.7.6)
     terminal-table (1.5.2)
@@ -371,4 +371,4 @@ DEPENDENCIES
   unicorn
 
 BUNDLED WITH
-   1.10.6
+   1.11.2

config/initializers/assets.rb

@@ -0,0 +1 @@
+Rails.application.config.assets.precompile += %w( validation.js jquery.dataTables.js )