Fix #40 Update semantic to v1.4.0

Author: jhx

github-css-rails.gemspec

@@ -30,6 +30,6 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'rake', '~> 10.3.2'
   spec.add_development_dependency 'rspec-rails', '~> 3.1.0'
   spec.add_development_dependency 'rubocop', '~> 0.26.1'
-  spec.add_development_dependency 'semantic', '~> 1.3.1'
+  spec.add_development_dependency 'semantic', '~> 1.4.0'
   spec.add_development_dependency 'sqlite3', '~> 1.3.9'
 end