Test under Rails 4.2.x

While previously Gemfile forced tests to run under 4.0.x, in fact they seem to only pass under 4.2.x.

(This one-line change took me a day to figure out!)

Author: jrochkind

Gemfile

@@ -5,7 +5,7 @@ gemspec
 gem 'jruby-openssl', :platform => :jruby
 
 group :test do
-  gem 'activerecord', '~> 4.0.0'
+  gem 'activerecord', '~> 4.2.0'
   gem 'activerecord-jdbcsqlite3-adapter', :platform => [:jruby]
   gem 'libxml-ruby', :platform => [:ruby, :mswin]
   gem 'rake'