Stick fog to 1.3.1

Gemfile.lock

@@ -143,7 +143,7 @@ DEPENDENCIES
   cocaine (~> 0.2)
   cucumber (~> 1.2.1)
   fakeweb
-  fog
+  fog (= 1.3.1)
   jruby-openssl
   launchy
   mocha

paperclip.gemspec

@@ -43,7 +43,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency('capybara')
   s.add_development_dependency('bundler')
   s.add_development_dependency('cocaine', '~> 0.2')
-  s.add_development_dependency('fog')
+  s.add_development_dependency('fog', '1.3.1')
   s.add_development_dependency('pry')
   s.add_development_dependency('launchy')
   s.add_development_dependency('rake')