Fixes uninitialized constant Rack::Timeout::Error

ruby-openid#5

In an application where I'm using this gem, I'm also using the
rack-timeout gem (https://github.com/kch/rack-timeout), so use of
Timeout inside the Rack::OpenID class was finding Rack::Timeout,
which is not the same. This commit updates references to Timeout to
use the root namespace (::Timeout).

Conflicts:
	lib/rack/openid.rb

Author: jeffcarbs

lib/rack/openid.rb

@@ -126,7 +126,7 @@ def begin_authentication(env, qs)
           add_oauth_fields(oidreq, params)
           url = open_id_redirect_url(req, oidreq, params["trust_root"], params["return_to"], params["method"], immediate)
           return redirect_to(url)
-        rescue ::OpenID::OpenIDError, Timeout::Error => e
+        rescue ::OpenID::OpenIDError, ::Timeout::Error => e
           env[RESPONSE] = MissingResponse.new
           return @app.call(env)
         end
@@ -270,7 +270,7 @@ def default_store
 
       def timeout_protection_from_identity_server
         yield
-      rescue Timeout::Error
+      rescue ::Timeout::Error
         TimeoutResponse.new
       end
   end