Improve the notification example in README

README.md

@@ -51,17 +51,40 @@ Pushpad.signature_for current_user.id
 
 ```ruby
 notification = Pushpad::Notification.new({
+  # required, the main content of the notification
   body: "Hello world!",
-  title: "Website Name", # optional, defaults to your project name
-  target_url: "https://example.com", # optional, defaults to your project website
-  icon_url: "https://example.com/assets/icon.png", # optional, defaults to the project icon
-  badge_url: "https://example.com/assets/badge.png", # optional, defaults to the project badge
-  image_url: "https://example.com/assets/image.png", # optional, an image to display in the notification content
-  ttl: 604800, # optional, drop the notification after this number of seconds if a device is offline
-  require_interaction: true, # optional, prevent Chrome on desktop from automatically closing the notification after a few seconds
-  silent: false, # optional, enable this option if you want a mute notification without any sound
-  urgent: false, # optional, enable this option only for time-sensitive alerts (e.g. incoming phone call)
-  custom_data: "123", # optional, a string that is passed as an argument to action button callbacks
+
+  # optional, the title of the notification (defaults to your project name)
+  title: "Website Name",
+
+  # optional, open this link on notification click (defaults to your project website)
+  target_url: "https://example.com",
+
+  # optional, the icon of the notification (defaults to the project icon)
+  icon_url: "https://example.com/assets/icon.png",
+
+  # optional, the small icon displayed in the status bar (defaults to the project badge)
+  badge_url: "https://example.com/assets/badge.png",
+
+  # optional, an image to display in the notification content
+  # see https://pushpad.xyz/docs/sending_images
+  image_url: "https://example.com/assets/image.png",
+
+  # optional, drop the notification after this number of seconds if a device is offline
+  ttl: 604800,
+
+  # optional, prevent Chrome on desktop from automatically closing the notification after a few seconds
+  require_interaction: true,
+
+  # optional, enable this option if you want a mute notification without any sound
+  silent: false,
+
+  # optional, enable this option only for time-sensitive alerts (e.g. incoming phone call)
+  urgent: false,
+
+  # optional, a string that is passed as an argument to action button callbacks
+  custom_data: "123",
+
   # optional, add some action buttons to the notification
   # see https://pushpad.xyz/docs/action_buttons
   actions: [
@@ -72,10 +95,14 @@ notification = Pushpad::Notification.new({
       action: "myActionName" # optional
     }
   ],
-  starred: true, # optional, bookmark the notification in the Pushpad dashboard (e.g. to highlight manual notifications)
+
+  # optional, bookmark the notification in the Pushpad dashboard (e.g. to highlight manual notifications)
+  starred: true,
+
   # optional, use this option only if you need to create scheduled notifications (max 5 days)
   # see https://pushpad.xyz/docs/schedule_notifications
   send_at: Time.utc(2016, 7, 25, 10, 9),
+
   # optional, add the notification to custom categories for stats aggregation
   # see https://pushpad.xyz/docs/monitoring
   custom_metrics: ['examples', 'another_metric'] # up to 3 metrics per notification