Push Notification: fix compatibility with latest Android

[ichan-mb]

We also needed this PR: fuse-open/uno#504 to make it works

Now, on Android 13 later, we can lazy request permission for push notifications same with iOS. First, define it on the unoproj

"Android": {
  "PushNotifications": {
      "RegisterOnLaunch": false
    }
}

and in your App, you can call the register method to ask for permission. Example:

<App>
	<JavaScript>

		var push = require("FuseJS/Push");
		var Observable = require("FuseJS/Observable")

		var log = new Observable()

		push.on("registrationSucceeded", function(regID) {
			console.log("Reg Succeeded: " + regID);
			log.value = "Reg Succeeded: " + regID
		});

		push.on("error", function(reason) {
			console.log("Reg Failed: " + reason);
			log.value = "Reg Failed: " + reason
		});

		push.on("receivedMessage", function(payload) {
			console.log("Recieved Push Notification: " + payload);
			log.value = "Recieved Push Notification: " + payload
		});

		module.exports.log = log
		module.exports.register = function() {
			push.register()
		}

	</JavaScript>
	<ClientPanel>
		<StackPanel>
			<Text Value="{log}" />
			<Button Text="Register Notification" Clicked="{register}" />
		</StackPanel>
	</ClientPanel>
</App>

This PR contains:

• Changelog
• Documentation
• Tests