Add some extra usage/clarification

README.md

@@ -38,6 +38,10 @@ process can receive `system_monitor` messages.  But using the
 `system_monitor` events, each party can add an event handler to the
 `riak_sysmon_handler` event handler.
 
+The event handler process in this application uses the registered name
+`riak_sysmon_handler`.  To add your handler, use something like:
+`gen_event:add_sup_handler(riak_sysmon_handler, yourModuleName, YourInitialArgs)`.
+
 See the
 [`gen_event` documentation for `add_up_event/3`](http://www.erlang.org/doc/man/gen_event.html#add_sup_handler-3)
 for API details.  See the example event handler module in the source

doc/overview.edoc

@@ -56,3 +56,12 @@ messages inform your event handler that `Num' events of a certain type
 (`proc_events' or `port_events') were suppressed in the last second
 (i.e. their arrival rate exceeded the configured rate limit). </li>
 </ul>
+
+The event handler process in this application uses the registered name
+`riak_sysmon_handler'.  To add your handler, use something like:
+`gen_event:add_sup_handler(riak_sysmon_handler, yourModuleName, YourInitialArgs)'.
+
+See
+{@link gen_event:add_sup_handler/3}
+for API details.  See the example event handler module in the source
+repository, `src/riak_sysmon_example_handler.erl', for example usage.