Gemfile.rails-3.x in workflow-1.2.0

- old
+ new

@@ -5,7 +5,7 @@
   gem "bundler", ">= 1.0.0"
   gem "activerecord", "~>3.2"
   gem "sqlite3"
   gem "mocha"
   gem "rake"
-  gem "ruby-graphviz", ">= 1.0"
+  gem "ruby-graphviz", "~> 1.0.0"
 end