Should use the "new" way of writing bindings

[ryancrawcour]

Currently uses the "old" method of writing bindings, which some earlier bindings (SB/Storage/etc) all still use.

There is a newer way to do this that doesn't require nearly as much code, and there is support for open generics.

You can see an example in the cosmos binding for a collector, which starts here: https://github.com/Azure/azure-webjobs-sdk-extensions/blob/dev/src/WebJobs.Extensions.CosmosDB/Config/CosmosDBExtensionConfigProvider.cs#L56

There's also some documentation on how to do this here: https://github.com/Azure/azure-webjobs-sdk/wiki/Creating-custom-input-and-output-bindings#binding-to-generic-types-with-opentypes

We should update this "old" method of doing bindings to the "new" method.