Added support for connection_ref's down throughout

the code, so models can connect to specific Redis
servers.

I believe a lot of the code needs some
restructuring at some point down the line to
handle multiple connections in a cleaner way, but
for now it'll do.

spec/model_helper.rb

@@ -1,6 +1,6 @@
 require "redistat"
 
-class ModelHelper
+class ModelHelper1
   include Redistat::Model
   
   
@@ -13,4 +13,11 @@ class ModelHelper2
   store_event true
   hashed_label true
   
+end
+
+class ModelHelper3
+  include Redistat::Model
+  
+  connect_to :port => 8379, :db => 14
+  
 end