notify: add os.Signal like example to notify documentation

Adds to godoc-generated documentation a very basic example which
is similar to the one created in os.Signal package.

event.go

@@ -53,7 +53,7 @@ var estr = map[Event]string{
 
 // String implements fmt.Stringer interface.
 func (e *event) String() string {
-	return e.Event().String() + `, "` + e.Path() + `"`
+	return e.Event().String() + `: "` + e.Path() + `"`
 }
 
 // Kind gives generic event type of the EventInfo.Event(). The purpose is to

example_test.go

@@ -0,0 +1,28 @@
+// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+package notify_test
+
+import (
+	"log"
+
+	"github.com/rjeczalik/notify"
+)
+
+func ExampleWatch() {
+	// Create a channel which will be used to receive file system notifications.
+	// The channel must be buffered since the notify package does not block when
+	// sending events. Thus, if an event is created and there is no one who can
+	// receive it, the event will be dropped.
+	c := make(chan notify.EventInfo, 1)
+	// We are going to watch our working directory recursively trying to catch
+	// either Create or Write event.
+	if err := notify.Watch("./...", c, notify.Create, notify.Write); err != nil {
+		log.Fatal(err)
+	}
+
+	// Block until an event is received.
+	ei := <-c
+	log.Println("Got event:", ei)
+}