Merge pull request hapijs#481 from wpreul/feature/413

Adding log tag filtering information to readme

docs/Reference.md

@@ -279,7 +279,7 @@ optional settings:
 - `requestsEvent` - the event type used to capture completed requests. Defaults to 'tail'. Options are:
     - 'response' - the response was sent but request tails may still be pending.
     - 'tail' - the response was sent and all request tails completed.
-- `subscribers` - an object where each key is a destination and each value an array subscriptions. Subscriptions available are _ops_, _request_, and _log_. The destination can be a URI or _console_. Defaults to a console subscription to all three. To disable the console output for the server instance pass an empty array into the subscribers "console" configuration. 
+- `subscribers` - an object where each key is a destination and each value is either an array or object with an array of subscriptions. The subscriptions that are available are _ops_, _request_, and _log_. The destination can be a URI or _console_. Defaults to a console subscription to all three. To disable the console output for the server instance pass an empty array into the subscribers "console" configuration. 
 
 For example:
 ```javascript
@@ -305,6 +305,18 @@ var options = {
 };
 ```
 
+Log messages are created with tags.  Usually a log will include a tag to indicate if it is related to an error or info along with where the message originates.  If, for example, the console should only output error's that were logged you can use the following configuration:
+```javascript
+var options = {
+    monitor: {
+        subscribers: {
+            console: { tags: ['error'], events: ['log'] }
+        }
+    }
+};
+```
+
+
 
 ### Authentication