Add JSON dependency.

Author: defunkt

resque.gemspec

@@ -25,6 +25,7 @@ Gem::Specification.new do |s|
   s.add_dependency "redis-namespace", "~> 0.4.0"
   s.add_dependency "vegas",           "~> 0.1.2"
   s.add_dependency "sinatra",         ">= 0.9.2"
+  s.add_dependency "json",            "~> 1.1.3"
 
   s.description = <<description
     Resque is a Redis-backed Ruby library for creating background jobs,