First check if the formatter is defined on the model, then fallback to the globa…

…l formatter if it exists.

@@ -32,10 +32,10 @@ class Rivets.Binding
     for formatter in @formatters
       args = formatter.split /\s+/
       id = args.shift()
-      value = if Rivets.config.formatters[id]
-        Rivets.config.formatters[id] value, args...
-      else
+      value = if @model[id] instanceof Function
         @model[id] value, args...
+      else if Rivets.config.formatters[id]
+        Rivets.config.formatters[id] value, args...
 
     value