Feature: Add complex notifications

[pathartl]

Photino's ability to create notifications is extremely basic and only allows setting the title and message. This PR aims to add support for more complex Windows notifications.

Breaking changes:

• Photino::ShowNotification has been removed
• WinToastLib has been updated to v1.3.2

Implementation:
PhotinoWindow has a new method called CreateNotification that is used to build a notification. The notification can then be shown by calling Show(). Action buttons can also be added to the notification with a callback.

Example:

window
    .CreateNotification(PhotinoNotificationType.ToastImageAndText04)
    .AddText("Photino.Native")
    .AddText("This is the first line of a test notification")
    .AddText("This is the second line of a test notification")
    .AddText("via Photino") // On Windows, the fourth line of text gets set to the attribution text
    .SetImagePath("testImage.jpg")
    .AddAction("Show" (notification) =>
    {
        Log("Show button clicked!");
    })
    .AddAction("Hide")
    .Show();

On the C++ side, in keeping with the intention of Photino being cross platform a layer of abstraction on top of WinToastLib has been created. Photino now has its own PhotinoNotification type. This should allow notifications for Linux and macOS to be added later on. I tried to keep the implementation as platform agnostic as possible, so some changes may need to be made to the enum namings, but names are currently heavily borrowed from Windows/WinToastLib.