Fix GoDoc to match actual events-limit

Commit 59d45c384a2de7bca73296ce1471646db14cb0c8 changed
the `eventsLimit` from 64 to 256, but did not update
the GoDoc accordingly.

This patch updates the GoDoc for `Subscribe` and `SubscribeTopic`
to match the actual limit.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
diff --git a/daemon/events/events.go b/daemon/events/events.go
index d1529e1..6a4990f 100644
--- a/daemon/events/events.go
+++ b/daemon/events/events.go
@@ -28,7 +28,7 @@
 	}
 }
 
-// Subscribe adds new listener to events, returns slice of 64 stored
+// Subscribe adds new listener to events, returns slice of 256 stored
 // last events, a channel in which you can expect new events (in form
 // of interface{}, so you need type assertion), and a function to call
 // to stop the stream of events.
@@ -46,7 +46,7 @@
 	return current, l, cancel
 }
 
-// SubscribeTopic adds new listener to events, returns slice of 64 stored
+// SubscribeTopic adds new listener to events, returns slice of 256 stored
 // last events, a channel in which you can expect new events (in form
 // of interface{}, so you need type assertion).
 func (e *Events) SubscribeTopic(since, until time.Time, ef *Filter) ([]eventtypes.Message, chan interface{}) {