Depend on rdf-turtle 3.1.

Author: gkellogg

rdf.gemspec

@@ -32,7 +32,7 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency     'link_header', '~> 0.0', '>= 0.0.8'
   gem.add_runtime_dependency     'hamster',     '~> 3.0'
   gem.add_development_dependency 'rdf-spec',    '~> 3.1'
-  gem.add_development_dependency 'rdf-turtle',  '~> 3.0'
+  gem.add_development_dependency 'rdf-turtle',  '~> 3.1'
   gem.add_development_dependency 'rdf-vocab',   '~> 3.0'
   gem.add_development_dependency 'rdf-xsd',     '~> 3.0'
   gem.add_development_dependency 'rest-client', '~> 2.1'