Adding 'name' property to <Exceptional> config section.

We like to put the environment in our application names. Things like "REST API (dev)" and "REST API (prod)".

The problem is that when we want to do an xdt transformation on our web.configs, we have no elements to transform on since application name will vary per environment.

Adding an optional "name" property to allow xdt transformations.  Shouldn't break existing configs and allows application name to change with environments.