Added Title Support For systray icon , Syntax highlighting in README and a few spelling Corrections

[mastermach50]

Made it possible to add a title of your own for the systray icon rather than just tooltip.
example:

from win10toast import ToastNotifier

notifier = ToastNotifier("Application Name")
notifier.show_toast(
    "Notification",
    "Message",
    icon_path = "Keyboard A Key.ico",
    duration = 10,
    threaded = True)

Also did a few spelling corrections.(In README and init)