Namespace-level tier selection enabled for Notification Hubs

Azure Notification Hubs recently enabled [namespace-level tiers](https://azure.microsoft.com/en-us/pricing/details/notification-hubs/). Each subscription used to have all of its namespaces and hubs tied to one tier (free, basic, or standard), but that wasn't the most efficient way for our customers to handle resources. With namespace-level tiers, customers can allocate resources tailored to each namespace’s expected traffic and usage patterns. See the full details in the [blog post](https://azure.microsoft.com/en-us/blog/namespace-level-tier-selection-enabled-for-push-notification-hubs/). * App Service * Notification Hubs * Features * [ App Service](https://azure.microsoft.com/en-gb/products/app-service/) * [ Notification Hubs](https://azure.microsoft.com/en-gb/services/notification-hubs/)