Add index access to dynamic properties in the Liquid notification templates

[tatarincev]

@tatarincev commented on Tue Mar 27 2018

Currently, if any object in notification has dynamic properties you can't use them by this syntax
order.dynamic_properties.property_name or order.dynamic_properties[property_name]

Technical solution:
In this code need to for all IHasDynamicProperties objects do somehow conversation to Dictionary before adding this object to render context.
https://github.com/VirtoCommerce/vc-platform/blob/dev/VirtoCommerce.Platform.Data.Notifications/LiquidNotificationTemplateResolver.cs#L37