Merge pull request #258 from rspec/pin_nokogiri

Prevent bad version of nokogiri and fix build

Author: JonRowe

Gemfile

@@ -15,7 +15,7 @@ end
 
 ### dep for ci/coverage
 gem 'simplecov', '~> 0.8'
-gem "nokogiri", (RUBY_VERSION < '1.9.3' ? "1.5.2" : ["~> 1.5", "!= 1.6.6.3", "!= 1.6.6.4"])
+gem "nokogiri", (RUBY_VERSION < '1.9.3' ? "1.5.2" : ["~> 1.5", "!= 1.6.6.3", "!= 1.6.6.4", "!= 1.6.7.1"])
 
 gem 'rubocop', "~> 0.23.0", :platform => [:ruby_19, :ruby_20, :ruby_21]