Bump rake from 11.3.0 to 12.3.0

Bumps [rake](https://github.com/ruby/rake) from 11.3.0 to 12.3.0.
- [Changelog](https://github.com/ruby/rake/blob/master/History.rdoc)
- [Commits](ruby/rake@v11.3.0...v12.3.0)

Gemfile

@@ -3,7 +3,7 @@ source "https://rubygems.org"
 ruby "2.2.7"
 
 gem 'rails', '~> 3.2'
-gem 'rake', '< 12.0'
+gem 'rake', '< 13.0'
 
 # Bundle edge Rails instead:
 # gem 'rails', :git => 'git://github.com/rails/rails.git'

Gemfile.lock

@@ -534,7 +534,7 @@ GEM
       rake (>= 0.8.7)
       rdoc (~> 3.4)
       thor (>= 0.14.6, < 2.0)
-    rake (11.3.0)
+    rake (12.3.0)
     ransack (1.8.4)
       actionpack (>= 3.0)
       activerecord (>= 3.0)
@@ -782,7 +782,7 @@ DEPENDENCIES
   rails-footnotes (>= 4.1.8)
   rails-i18n (~> 3.0.0)
   rails_12factor
-  rake (< 12.0)
+  rake (< 13.0)
   ransack
   redcarpet
   rspec-rails (~> 2.14.2)