Add ability to fully customize the Foreground Service notification

[jonahwh]

Introduces two new optional parameters to NotificationProperties' default constructor:

• notificationChannelId: This allows developers to customize the Notification Channel ID, so they can put the notification in the exact channel they desire
• notificationBuilderExtender: Accepts a lambda that can modify the Notification.Builder so developers can fully customize the Foreground Service notification

Usage Example:

override val notificationProperties get() = NotificationProperties(iconResId = R.drawable.plugin) { context ->
    setColor(Color.CYAN)
}

Will result in

[joaomgcd]

Thank you very much :) Makes sense!