add coffee-script dependency

ti.gemspec

@@ -18,10 +18,10 @@ Gem::Specification.new do |s|
   s.executables   = `git ls-files -- bin/*`.split("\n").map{ |f| File.basename(f) }
   s.require_paths = ["lib"]
 
-  # Currently we're not using these. However, I'd prefer to use these instead of 
+  # Currently we're not using these. However, I'd prefer to use these instead of
   # using the system command
   # s.add_runtime_dependency(%q<sass>,                ["~> 3.1.2"])
-  # s.add_runtime_dependency(%q<coffee-script>,       ["~> 2.2.0"])
+  s.add_runtime_dependency(%q<coffee-script>,       ["~> 2.2.0"])
 
   s.add_runtime_dependency(%q<colored>,             ["~> 1.2"])
   s.add_runtime_dependency(%q<rake>,                ["~> 0.8.7"]) # TODO: test with Rake 0.9.2